Journal articlePhysical review letters · June 2026
We investigate the time dependence of antiflatness in the entanglement spectrum, a measure for nonstabilizerness and lower bound for nonlocal quantum magic resource, on a subsystem of a linear SU(2) plaquette chain during thermalization. Tracing the time e ...
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Journal articlePhysical Review C · January 12, 2026
The early stage of a heavy-ion collision is marked by rapid entropy production and the transition from a gluon saturated initial condition to a plasma of quarks and gluons that evolves hydrodynamically. However, during the early times of the hydrod ...
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Journal articleEuropean Physical Journal Special Topics · December 1, 2025
In this article the title was incorrectly given as ‘The nonabelian plasma is chaotic egenstate thermalization in SU(2) gauge theory’ but should have been ‘The nonabelian plasma is chaotic: Eigenstate thermalization in SU(2) gauge theory’. The original arti ...
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Journal articleCommunications Physics · December 1, 2025
Understanding how isolated quantum systems thermalize is central to both fundamental physics and the development of quantum technologies. In this Perspective, we present recent and new results on thermalization in nonabelian gauge theory from exact real-ti ...
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Journal articlePhysical Review D · September 8, 2025
We investigate the transition between weak and strong coupling in thermal N ¼ 4 supersymmetric Yang-Mills theory as a function of ’t Hooft coupling λ for several quantities of phenomenological interest for which next-to-leading order calculations are avail ...
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Journal articlePhysical review letters · September 2025
We compute medium corrections to the energy-energy correlator (EEC) for jets in electron-nucleus collisions at leading order in the QCD coupling and the interaction of the jet with the medium. We derive an analytical expression for the modification of the ...
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Journal articleEuropean Physical Journal Special Topics · August 1, 2025
Nonabelian gauge theories are chaotic in the classical limit. We discuss new evidence from SU(2) lattice gauge theory that they are also chaotic at the quantum level. We also describe possible future studies aimed at discovering the consequences of this in ...
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Journal articleEuropean Physical Journal Special Topics · August 1, 2025
We study (nuclear) fusion reactions in beryllium. We argue that some are nuclear long-distance molecular processes of interest for low-energy nuclear reactions. For these, we develop a novel reaction model. We note a chain of reactions that can naturally a ...
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Journal articleJournal of High Energy Physics · August 1, 2025
We elaborate on the method introduced in arXiv:2403.02165 for holographic duals of Boundary Conformal Field Theories (BCFTs) with multiple boundaries. Naïvely, as the number of boundaries grow large such a calculation becomes unmanageable. We show that is ...
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Journal articleNuclear Physics A · July 1, 2024
This White Paper presents an overview of the current status and future perspective of QCD research, based on the community inputs and scientific conclusions from the 2022 Hot and Cold QCD Town Meeting. We present the progress made in the last decade toward ...
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Journal articlePhysical Review D · July 1, 2024
We study the entanglement entropy of Hamiltonian SU(2) lattice gauge theory in 2+1 dimensions on linear plaquette chains and show that the entanglement entropies of both ground and excited states follow Page curves. The transition of the subsystem size dep ...
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Journal articleJournal of High Energy Physics · May 1, 2024
In this work we introduce a method for calculating holographic duals of BCFTs with more than two boundaries. We apply it to calculating the dynamics of entanglement entropy in a 1+1d CFT that is instantaneously split into multiple segments and calculate th ...
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Journal articleEuropean Physical Journal C · March 1, 2024
We revisit the graphic table of QCD signatures in our 1996 Annual Reviews article “The Search for the Quark–Gluon Plasma” and assess the progress that has been made since its publication towards providing quantitative evidence for the formation of a quark– ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 2024
The nuclear equation of state (EOS) is at the center of numerous theoretical and experimental efforts in nuclear physics. With advances in microscopic theories for nuclear interactions, the availability of experiments probing nuclear matter under condition ...
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Journal articlePhysical Review D · January 1, 2024
We present preliminary numerical evidence for the hypothesis that the Hamiltonian SU(2) gauge theory discretized on a lattice obeys the eigenstate thermalization hypothesis (ETH). To do so we study three approximations: (a) a linear plaquette chain in a re ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · November 10, 2023
We make use of published yields for D-mesons and J/ψ in Pb+Pb collisions at ALICE and a schematic description of the expansion of the hadron gas to study D-meson collisions during the hadronic break-up phase as a production mechanism for charmonium in rela ...
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Journal articlePhysical Review D · November 1, 2023
We find a simple spin Hamiltonian to describe physical states of (2+1)-dimensional SU(2) lattice gauge theory on a honeycomb lattice with a truncation of the electric field representation at jmax=12. The simple spin Hamiltonian contains only local products ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · October 1, 2023
This article summarizes our present knowledge about nuclear matter at the highest energy densities and its formation in relativistic heavy ion collisions. We review what is known about the structure and properties of the quark-gluon plasma and survey the o ...
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Journal articlePhysical Review D · July 1, 2023
We explain how spin alignment of vector mesons can be induced by background fields, such as electromagnetic fields or soft gluon fields. Our study is based on the quantum kinetic theory of spinning quarks and antiquarks and incorporates the relaxation of t ...
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Journal articlePhysical Review D · April 1, 2023
We investigate the interaction of strong color fields in the glasma stage of high-energy nuclear collisions with the spins of quarks and antiquarks. We employ the perturbative solution of the quantum kinetic theory for the spin transport of (massive) quark ...
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Journal articlePhysical Review D · August 1, 2022
In this paper, Eq. (18) is missing a contribution from the surface term, which can be omitted when computing the axial current but has to be included when evaluating the quark spectrum. The correct form of the equation is (Formula Presented). We refer to [ ...
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Journal articlePhysical Review D · July 1, 2022
We investigate the electromagnetic response of a viscous quark-gluon plasma in the framework of the relativistic Boltzmann equation with current conserving collision term. Our formalism incorporates dissipative effects at all orders in linear response to t ...
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Journal articlePhysics Switzerland · June 1, 2022
I review the physics of the phase boundary between hadronic matter and quark matter from several different points of view. These include thermodynamics, statistical physics, and chemical kinetics. In particular, the review focuses on the role of the chemic ...
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Journal articlePhysical Review D · January 1, 2022
We study the important, yet widely overlooked, role of gluons for spin transport with a connection to local parity violation in quark gluon plasmas. We employ the formalism of quantum kinetic theory to quarks in weakly coupled quantum chromodynamics to der ...
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Journal articleAnnals of Physics · November 1, 2021
We investigate the response of a relativistic plasma to electromagnetic fields in the framework of the Boltzmann equation incorporating a collision term in the relaxation rate approximation selected in a form assuring current conservation. We obtain an exp ...
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Journal articlePhys. Rev. D · October 29, 2021
We study the important, yet widely overlooked, role of gluons for spin transport with a connection to local parity violation in quark gluon plasmas. We employ the formalism of quantum kinetic theory to quarks in weakly coupled quantum chromodynamics to der ...
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Journal articlePhysical Review D · October 1, 2021
The relation between the specific shear viscosity and the dimensionless jet quenching parameter in perturbative QCD is explored at next-to-leading order in the coupling constant. It is shown that the relation changes little, although both transport coeffic ...
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Journal article · June 22, 2021
Brief review of the hadronic probes that are used to diagnose the quark-gluon plasma produced in relativistic heavy ion collisions and interrogate its properties. Emphasis is placed on probes that have significantly impacted our understanding of the nature ...
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Journal article · September 11, 2020
Motivated by recent applications of the open quantum system formalism to
understand quarkonium transport in the quark-gluon plasma, we develop a set of
coupled Boltzmann equations for open heavy quark-antiquark pairs and quarkonia.
Our approach keeps track ...
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Journal article · April 14, 2020
We develop a framework of coupled transport equations for open heavy flavor
and quarkonium states, in order to describe their transport inside the
quark-gluon plasma. Our framework is capable of studying simultaneously both
open and hidden heavy flavor obs ...
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Journal articlePhysical Review D · April 1, 2020
This paper discusses possible phenomenological implications for p+A and A+A collisions of the results of recent numerical AdS/CFT calculations examining asymmetric collisions of planar shocks. In view of the extreme Lorentz contraction, we model highly rel ...
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Journal articlePhysical Review C · March 1, 2020
A systematic search for a critical point in the phase diagram of QCD matter is under way at the Relativistic Heavy Ion Collider (RHIC) and is planned at several future facilities. Its existence, if confirmed, and its location will greatly enhance our under ...
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Journal article · February 10, 2020
Using the open quantum system formalism and effective field theory of QCD, we
derive the Boltzmann transport equation of quarkonium inside the quark-gluon
plasma. Our derivation illuminates that the success of transport equations in
quarkonium phenomenolog ...
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Journal articlePublications of the Astronomical Society of Australia · 2020
AbstractGravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, w ...
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Journal articleEuropean Physical Journal Special Topics · July 1, 2019
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider ...
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Journal articleEuropean Physical Journal Special Topics · July 1, 2019
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider ...
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Journal articleEuropean Physical Journal C · June 1, 2019
We review the physics opportunities of the Future Circular Collider, covering its e+e-, pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and st ...
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Journal articleEuropean Physical Journal Special Topics · June 1, 2019
In response to the 2013 Update of the European Strategy for Particle Physics, the Future Circular Collider (FCC) study was launched, as an international collaboration hosted by CERN. This study covers a highest-luminosity high-energy lepton collider (FCC-e ...
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Journal articleNuclear Physics A · February 1, 2019
We develop a set of coupled Boltzmann equations to describe the dynamical evolution of heavy quarks and quarkonia inside the quark-gluon plasma. The quarkonium dissociation and recombination terms are calculated from pNRQCD. Their interplay drives the syst ...
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Journal articlePhysical Review D · October 1, 2018
We first compare different approaches to estimates of the magnitude of the chiral magnetic effect in relativistic heavy ion collisions and show that their main difference lies in the assumptions on the length of persistence of the magnetic field generated ...
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Journal articlePhysical Review D · September 25, 2018
II. STOPPING DISTANCES AT SMALL ANISOTROPY The second line of Eq. (5) should be (Formula Presented). A minor typo of B2(z) is corrected here. There were errors in the numerical code for computing the ratios of stopping distances by varying anisotropy with ...
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Journal articlePhysical Review D · April 1, 2018
We give an estimate of Ξcc++ production rate and transverse momentum spectra in relativistic heavy ion collisions. We use Boltzmann transport equations to describe the dynamical evolution of charm quarks and diquarks inside quark-gluon plasma. In-medium fo ...
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Journal articleEuropean Physical Journal A · February 1, 2018
We explore the fate of matter falling into a macroscopic Schwarzschild black hole for the simplified case of a radially collapsing thin spherical shell for which the back reaction of the geometry can be neglected. We treat the internal dynamics of the in-f ...
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Journal articlePhysical Review C · January 25, 2018
We calculate the dissociation and recombination rates of ϒ(1S) in quark-gluon plasma by using potential nonrelativistic QCD. We then study the dynamical in-medium evolution of the bb-ϒ system in a periodic box via the Boltzmann equation and explore how the ...
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Journal articleProceedings of Science · January 1, 2018
By coupling the Boltzmann transport equations of both quarkonium and open heavy quarks, we investigate their dynamical evolution inside the quark-gluon plasma and study quarkonium production in heavy ion collisions. The Boltzmann transport equation of quar ...
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Journal article · December 10, 2017
The yields for hadrons and even light nuclei measured at midrapidity in relativistic heavy ion collisions are found to be dictated exclusively by their thermal Boltzmann factor for a common temperature of approximately 155 MeV. The reason for the validity ...
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Journal articleInternational Journal of Modern Physics A · November 10, 2017
This is a short survey of signatures and characteristics of the quark-gluon plasma in the light of experimental results that have been obtained over the past three decades. In particular, we present an in-depth discussion of the strangeness observable, inc ...
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Journal articlePhysical Review D · June 1, 2017
We use effective field theory and thermal field theory to study the dynamical screening effect in the QED plasma on the α-α scattering at the Be8 resonance. Dynamical screening leads to an imaginary part of the potential which results in a thermal width fo ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · September 10, 2016
We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP) at weak coupling and N=4 super Yang–Mills plasma (SYMP) at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to ...
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Journal articleEuropean Physical Journal A · September 1, 2016
This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managem ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · May 25, 2016
We use effective field theory to study the a-a resonant scattering in a finitetemperature QED plasma. The static plasma screening effect causes the resonance state 8Be to live longer and eventually leads to the formation of a bound state when mD ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · June 9, 2015
We investigate the shear viscosity of leptons in a strongly coupled quark gluon plasma. We find that the shear viscosity due to the lepton-quark scattering is inversely proportional to the ratio of electric conductivity of the quark gluon plasma to tempera ...
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Journal articleProgress of Theoretical and Experimental Physics · November 7, 2014
I review some of the remarkable contributions of PHENIX to the discovery and exploration of the perfectly liquid quark-gluon plasma at RHIC. ...
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Journal articleNuclear Physics A · November 1, 2014
We argue that the domain structure of deconfined QCD matter, which can be inferred from the properties of the Polyakov loop, can simultaneously explain the two most prominent experimental features of the quark-gluon plasma, namely its near ideal fluid prop ...
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Journal articlePhysical Review C Nuclear Physics · July 29, 2014
Within five different approaches to parton propagation and energy loss in dense matter, a phenomenological study of experimental data on suppression of large-pT single inclusive hadrons in heavy-ion collisions at both the BNL Relativistic Heavy Ion Collide ...
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Journal articlePhysical Review C Nuclear Physics · April 3, 2014
We study elliptic and triangular flow in the collisions of deuteron-gold nuclei at sNN=200 GeV at RHIC and of proton-lead nuclei at sNN=5.02 TeV at the LHC, utilizing (3+1)-dimensional ideal hydrodynamics for the dynamic evolution of the fireball and a Mon ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 28, 2014
We compute the elliptic flow v2 of thermal photons in a strongly coupled plasma with constant magnetic field via gauge/gravity duality. The D3/D7 embedding is applied to generate the contributions from massive quarks. By considering the cases in 2+1 flavor ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 27, 2014
We discuss a mechanism for the apparently universal scaling in the high-multiplicity tail of charged particle distributions for high-energy nuclear collisions. We argue that this scaling behavior originates from rare fluctuations of the nucleon density. We ...
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Journal articlePhysical review letters · December 2013
To describe theoretically the creation and evolution of the quark-gluon plasma, one typically employs three ingredients: a model for the initial state, nonhydrodynamic early time evolution, and hydrodynamics. In this Letter we study the nonhydrodynamic ear ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · November 12, 2013
We study the thermalization process in classical Yang-Mills field theory starting from noisy glasmalike initial conditions by investigating the initial-value sensitivity of trajectories. Kunihiro et al. linked entropy generation to the Kolmogorov-Sinaï ent ...
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Journal articlePhysical Review C Nuclear Physics · October 30, 2013
We investigate the possibility of selecting heavy ion collision events with certain features in the initial state (event engineering). Anisotropic flow measurements in heavy ion reactions have confirmed the almost ideal fluid dynamical behavior of the hot ...
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Journal articleNuclear Physics A · August 1, 2013
We present a systematic study of dijet suppression at RHIC using the VNI/BMS parton cascade. We examine the medium modification of the dijet asymmetry A j and the energy distribution within the dijets (jet-shape). Understanding the sensitivity o ...
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Journal articleActa Physica Polonica B Proceedings Supplement · June 18, 2013
Polarization properties of turbulent stochastically inhomogeneous ultrarelativistic QED plasma are studied. It is shown that the sign of nonlinear turbulent Landau damping corresponds to an instability of the spacelike modes and, for sufficiently large tur ...
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Journal articleNuclear Physics A · May 2, 2013
We present a study of the dijet suppression at RHIC using the parton cascade model. We examine the modification of the dijet asymmetry A j and the fragmentation distributions z and j T in terms of: q̂; the path length of leading and su ...
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Journal articleInternational Journal of Modern Physics E · March 1, 2013
The Caldeira-Leggett (CL) model describes a microscopic quantum system, represented by a harmonic oscillator, in interaction with a heat bath, represented by a large number of harmonic oscillators with a range of frequencies. We consider the case when the ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · February 21, 2013
We present an analysis of the dynamics of the equifacial pentahedron on the Kapovich-Millson phase space under a volume preserving Hamiltonian. The classical dynamics of polyhedra under such a Hamiltonian may arise from the classical limit of the node volu ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · February 11, 2013
We employ the gauge/gravity duality to study the jet quenching of light probes traversing a static yet anisotropic strongly coupled N=4 super Yang-Mills plasma. We compute the stopping distance of an image jet induced by a massless source field, which is c ...
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Journal articleJournal of High Energy Physics · January 1, 2013
The sudden injection of energy in a strongly coupled conformal Feld theory and its subsequent thermalization can be holographically modeled by a shell falling into anti-de Sitter space and forming a black brane. For a homogeneous shell, Bhattacharyya and M ...
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Journal articlePhysica Scripta · January 1, 2013
This lecture presents an overview of the status of the investigation of the properties of the quark-gluon plasma using relativistic heavy ion collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider. It focuses on the insights that h ...
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Journal articleJournal of High Energy Physics · January 1, 2013
Using Wigner transforms of Green functions, we discuss non-equilibrium generalizations of spectral functions and occupation numbers. We develop methods for computing time-dependent spectral functions in conformal field theories holographically dual to thin ...
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Journal articleAnnual Review of Nuclear and Particle Science · December 3, 2012
At the end of 2010, the Large Hadron Collider (LHC) at CERN started operation with heavy-ion beams, colliding lead nuclei at a center-of-mass energy of 2.76 TeV per nucleon. These collisions ushered in a new era in ultrarelativistic heavy-ion physics at en ...
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Journal articleProceedings of Science · December 1, 2012
We present a panel discussion about our current state of knowledge about the Quark-Gluon Plasma. The nine panelists were asked to address the question: What do we want to know about the quark-gluon plasma, and how can we find the answers? The contributions ...
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Journal articlePhysical Review C Nuclear Physics · November 5, 2012
Background: There has been much recent investigation into dijets at the Large Hadron Collider, but predictions for dijets at Relativistic Heavy Ion Collider (RHIC) scales are lacking. Purpose: We present a systematic study of the dijet suppression at RHIC ...
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Journal articleScience (New York, N.Y.) · July 2012
When nuclear matter is heated beyond 2 trillion degrees, it becomes a strongly coupled plasma of quarks and gluons. Experiments using highly energetic collisions between heavy nuclei have revealed that this new state of matter is a nearly ideal, highly opa ...
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Journal articlePhysical Review C Nuclear Physics · June 11, 2012
We study how local fluctuations in the initial states of relativistic heavy-ion collisions manifest in the correlations between different orders of harmonic moments of the density profiles, particularly those involving only odd harmonics that arise purely ...
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Journal articleAip Conference Proceedings · May 10, 2012
We have implemented the LPM effect into a microscopic transport model with partonic degrees of freedom by following the algorithm of Zapp & Wiedemann. The Landau-Pomeranchuk-Migdal (LPM) effect is a quantum interference process that modifies the emission o ...
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Journal articlePhysical Review C Nuclear Physics · May 4, 2012
We develop the relativistic theory of hydrodynamic fluctuations for application to high-energy heavy-ion collisions. In particular, we investigate their effect on the expanding boost-invariant (Bjorken) solution of the hydrodynamic equations. We discover t ...
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Journal articleActa Physica Polonica B · April 1, 2012
The relativistic theory of hydrodynamic fluctuations, or noise, is derived and applied to high energy heavy ion collisions. These fluctuations are inherent in any space-time varying system and are present in addition to initial state fluctuations. We illus ...
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Journal articlePhysical review. E, Statistical, nonlinear, and soft matter physics · January 2012
The Husimi distribution provides for a coarse-grained representation of the phase-space distribution of a quantum system, which may be used to track the growth of entropy of the system. We present a general and systematic method of solving the Husimi equat ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · January 1, 2012
We compute the probability of J/ production from the interaction between c and the strong magnetic field generated in relativistic heavy ion collisions. The computation is first carried out in the heavy quark effective model, in which the M1 rad ...
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Journal articleInternational Journal of Modern Physics E · November 1, 2011
We review current ideas on entropy production during the different stages of a relativistic nuclear collision. This includes recent results on decoherence entropy and the entropy produced during the hydrodynamic phase by viscous effects. We start by a disc ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · July 25, 2011
Using the AdS/CFT correspondence, we probe the scale dependence of thermalization in strongly coupled field theories following a sudden injection of energy via calculations of two-point functions, Wilson loops, and entanglement entropy in d=2, 3, 4. In the ...
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Journal articlePhysical review letters · May 2011
Using the holographic mapping to a gravity dual, we calculate 2-point functions, Wilson loops, and entanglement entropy in strongly coupled field theories in d=2, 3, and 4 to probe the scale dependence of thermalization following a sudden injection of ener ...
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Journal articlePhysical review letters · April 2011
We investigate the medium modification of a partonic jet shower traversing in a hot quark-gluon plasma. We derive and solve a differential equation that governs the evolution of the radiated gluon distribution as the jet propagates through the medium. Ener ...
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Journal articleNuclear Physics A · March 15, 2011
Turbulent color fields, which can arise in the early and late stages of relativistic heavy ion collisions, may contribute significantly to the transport processes in the matter created in these collisions. We review the theory of these anomalous transport ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · January 24, 2011
The B11(p,α)αα reaction at energies between 200 keV and a few MeV has a very long history, dating back to studies by Lord Rutherford and Dee and Gilbert in the 1930s. It is shown that the modern view of this reaction, established in 1987, is inc ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · December 17, 2010
Understanding the underlying mechanisms causing rapid thermalization deduced for high-energy heavy ion collisions is still a challenge. To estimate the thermalization time, entropy growth for classical Yang-Mills theories is studied, based on the determina ...
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Journal articlePhysical Review C Nuclear Physics · December 13, 2010
We develop a systematic framework for the study of the initial collision geometry fluctuations in relativistic heavy-ion collisions and investigate how they evolve through different stages of the fireball history and translate into final-particle momentum ...
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Journal articlePhysical review letters · December 2010
Finite temperature lattice simulations of quantum chromodynamics (QCD) are sensitive to the hadronic mass spectrum for temperatures below the "critical" temperature T(c) ≈ 160 MeV. We show that a recent precision determination of the QCD trace anomaly show ...
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Journal articlePhysical Review C Nuclear Physics · November 29, 2010
We derive a nonlocal effective Lagrangian for the chiral magnetic effect. An electric field is generated by winding number fluctuations of the nonabelian gauge field in the presence of a strong magnetic field. We estimate the magnitude of charge asymmetry ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · October 1, 2010
We study the time evolution of a high-momentum gluon or quark propagating through an infinite, thermalized, partonic medium utilizing a Boltzmann equation approach. We calculate the collisional energy loss of the parton, study its temperature and flavor de ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · March 18, 2010
We derive the transport equations of quark-gluon plasma in the quasilinear approximation. The equations are either of the Balescu-Lenard or Fokker-Planck form. The plasma's dynamics is assumed to be governed by longitudinal chromoelectric fields. The isotr ...
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Journal article · January 14, 2010
We explore the properties of physical theories in space-times with two time dimensions. We show that the common arguments used to rule such theories out do not apply if the dynamics associated with the additional time dimension is thermal or chaotic and do ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2010
We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both the hadronic gas and the partonic p ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2010
The first calculation of triangular flow ν3 in Au+Au collisions at √sNN = 200A GeV from an event-by-event (3 + 1) d transport+hydrodynamics hybrid approach is presented. As a response to the initial triangularity Ie{cyrillic, ukrainian}3 of the ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · December 17, 2009
The average transverse momentum transfer per unit path length to a fast parton scattering elastically in a perturbative quark-gluon plasma is related to the radiative energy loss of the parton. We first calculate the momentum transfer coefficient q^ in ter ...
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Journal articleGauge Theory of Weak Interactions · December 1, 2009
"Gauge Theory of Weak Interactions" treats the unification of electromagnetic and weak interactions and considers related phenomena. First, the Fermi theory of beta decay is presented, followed by a discussion of parity violation, clarifying the importance ...
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Journal articleNuclear Physics A · November 1, 2009
We review what is known about the contributions to the final entropy from the different stages of a relativistic nuclear collision, including recent results on the decoherence entropy and the entropy produced during the hydrodynamic phase by viscous effect ...
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Journal articleNuclear Physics A · November 1, 2009
The presence of a critical point in the QCD phase diagram can deform the trajectories describing the evolution of the expanding fireball in the μB - T phase diagram. The deformation of the hydrodynamic trajectories will change the transverse vel ...
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Journal articleNuclear Physics A · November 1, 2009
The total energy deposited into the medium per unit length by a fast parton traversing a quarkgluon plasma is calculated. We take the medium excitation due to collisions to be given by the well known expression for the collisional drag force. The parton's ...
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Journal articleNuclear Physics A · November 1, 2009
We study the gluonic sector of the three-flavor PNJL model by obtaining the adjoint Polyakov loop and the gluon distribution function in the mean-field approximation. Besides, we explore the thermal strange quark pair-production processes, q over(q, -) → s ...
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Journal articlePhysical review letters · July 2009
We calculate the total energy deposited into the medium per unit length by fast partons traversing a quark-gluon plasma. The medium excitation due to collisions is taken to be given by the well-known expression for the collisional drag force. The radiative ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · June 15, 2009
We study the temperature dependence of the adjoint Polyakov loop and its implication for the momentum spectrum of gluons in the mean-field approximation. This allows us to calculate the contribution of the thermal (transverse) gluons to the thermodynamic p ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · June 15, 2009
The recombination model as a model for hadronization from a quark-gluon plasma has been recently revived since it has advantages in explaining several important features of the final state produced in heavy-ion collisions at the RHIC, such as the constitue ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · June 15, 2009
Quarks of other flavours than up and down, i.e. s, c and b quarks, have been long recognized as effective probes of the structure of hot QCD matter. In this paper, I review some of the motivations for their investigation and discuss the salient results obt ...
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Journal articleProgress in Particle and Nuclear Physics · April 1, 2009
The QCD matter produced in nuclear collisions at the Relativistic Heavy Ion Collider (RHIC) has been found to have a very low shear viscosity, which is close to the lower bound allowed by unitarity. The matter has also been found to strongly suppress the e ...
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Journal articlePhysical Review C Nuclear Physics · March 3, 2009
Short thermalization times of less than 1 fm/c for quark and gluon matter have been suggested by recent experiments at the Relativistic Heavy Ion Collider. It has been difficult to justify this rapid thermalization in first-principle calculations based on ...
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Journal articleProgress of Theoretical Physics · March 1, 2009
We propose a broadly applicable formalism for the description of coarse grained entropy production in quantum mechanical processes. Our formalism is based on the Husimi transform of the quantum state, which encodes the notion that information about any qua ...
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Journal articleSoryushiron Kenkyu · February 20, 2009
The presence of a critical point in the QCD phase diagram can deform the trajectories describing the evolution of the expanding fireball in the μ_B-T phase diagram. If the average emission time of hadrons is a function of transverse velocity, as microscopi ...
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Journal articlePhysical Review C Nuclear Physics · October 13, 2008
We derive the space-time distribution of energy and momentum deposited by a fast parton traversing a weakly coupled quark-gluon plasma by treating the fast parton as the source of an external color field perturbing the medium. We then use our result as a s ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · October 1, 2008
The spacetime distribution of energy and momentum deposited by a fast parton traversing a weakly coupled quark-gluon plasma is calculated by treating the fast parton as the source of an external color field perturbing the medium. When the result is used as ...
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Journal articlePhysical Review C Nuclear Physics · September 26, 2008
We discuss the influence of different initial conditions for the stress tensor and the effect of bulk viscosity on the expansion and cooling of the fireball created in relativistic heavy ion collisions. In particular, we explore the evolution of longitudin ...
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Journal articlePhysical review letters · September 2008
The presence of a critical point in the QCD phase diagram can deform the trajectories describing the evolution of the expanding fireball in the mu_B-T phase diagram. If the average emission time of hadrons is a function of transverse velocity, as microscop ...
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Journal articlePhysical Review C Nuclear Physics · June 19, 2008
The photon bremsstrahlung rate from a quark jet produced in deep-inelastic scattering (DIS) off a large nucleus is studied in the collinear limit. The leading medium-enhanced higher twist corrections that describe the multiple scattering of the jet in the ...
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Journal articlePhysical Review C Nuclear Physics · May 23, 2008
The transverse broadening of jets produced in deep-inelastic scattering (DIS) off a large nucleus is studied in the collinear limit. A class of medium enhanced higher twist corrections are resummed to calculate the transverse momentum distribution of the p ...
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Journal articleProgress of Theoretical Physics Supplement · January 1, 2008
In this lecture, I discuss how the RHIC data are challenging our theoretical understanding of QCD matter. Important components of this challenge include how equilibrated QCD matter is formed, whether its statistical and dynamical properties permit a quasi- ...
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Journal articleActa Physica Polonica B · December 1, 2007
After reviewing some basic concepts of the theory of strongly interacting matter above nuclear energy density and reviewing some salient results of the experimental program at the Relativistic Heavy Ion Collider (RHIC), these lectures explain why the quark ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · August 1, 2007
We argue that an expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated colour fields. The anomalous viscosity dominates over the collisional viscosity for large velocity gradients or weak couplin ...
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Journal articlePhysical review letters · July 2007
The nearside distribution of particles at intermediate transverse momentum, associated with a high momentum trigger hadron produced in a high energy heavy-ion collision, is broadened in rapidity compared with the jet cone. This broadened distribution is th ...
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Journal articleAnnual Review of Nuclear and Particle Science · December 27, 2006
This review describes the current status of the heavy ion research program at the Relativistic Heavy Ion Collider (RHIC). The new suite of experiments and the collider energies have opened up new probes of the medium created in the collisions. Our review f ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · December 1, 2006
Flavour probes depend on the transport properties of the quark-gluon plasma. An expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated colour fields. The anomalous viscosity dominates over the col ...
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Journal articlePhysical Review C Nuclear Physics · November 15, 2006
The ratios of off-diagonal to diagonal conserved charge susceptibilities, e.g., χBS/χS,χQS/χS, related to the quark flavor susceptibilities, have proven to be discerning probes of the flavor carrying degrees of freedom in hot strongly interacting matter. V ...
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Journal articleProgress of Theoretical Physics · October 1, 2006
We derive an expression for the anomalous viscosity in an anisotropically expanding quark-gluon-plasma, which arises from interactions of thermal partons with dynamically generated color fields. The anomalous viscosity dominates over the collisional viscos ...
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Journal articleNuclear Physics A · August 7, 2006
We describe how parton recombination can address the recent measurement of dynamical jet-like two particle correlations. In addition we discuss the possible effect realistic light-cone wave-functions including higher Fock-states may have on the well-known ...
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Journal articleNuclear Physics A · August 7, 2006
This is a review of the latest developments in the theory of superdense nuclear matter, formed in relativistic heavy ion collisions or in the core of collapsed stars, as they were reported and discussed at the Quark Matter 2005 conference in Budapest (Hung ...
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Journal articlePhysical review letters · June 2006
We argue that an expanding quark-gluon plasma has an anomalous viscosity, which arises from interactions with dynamically generated color fields. We derive an expression for the anomalous viscosity in the turbulent plasma domain and apply it to the hydrody ...
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Journal articlePhysical Review C Nuclear Physics · May 31, 2006
We calculate the decoherence time of the ground state wave function of a nucleus in a high energy heavy ion collision. We define this time as the decay time of the ratio TrD2/TrD)2 of traces of the density matrix D. We find that this time is smaller or equ ...
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Journal articleJournal of Physics A Mathematical and General · May 5, 2006
We study the semiclassical Wigner-Kirkwood (WK) expansion of the partition function Z(t) for arbitrary even homogeneous potentials, starting from the Bloch equation. As is well known, the phase-space kernel of Z satisfies the so-called Uhlenbeck-Beth equat ...
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Journal articleJournal of Physics A Mathematical and General · January 6, 2006
We study the quantum mechanical motion in the x2y2 potentials with n ≤ 2, 3, which arise in the spatially homogeneous limit of the Yang-Mills (YM) equations. These systems show strong stochasticity in the classical limit (ℏ ≤ 0) and e ...
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Journal articleJournal of Physics A Mathematical and General · January 6, 2006
We continue our study of the quantum mechanical motion in the x 2y2 potentials for n ≤ 2, 3, which arise in the spatially homogeneous limit of the Yang-Mills (YM) equations. In the present paper, we develop a new approach to the calcu ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2006
We explore the range of values of the in-medium width of a ρ-meson at rest which is compatibale with the QCD sum rule approach in a nuclear medium assuming vector meson dominance and a Brown-Rho scaling law of the ρ-meson mass with the chiral condensate. T ...
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Journal articleActa Physica Hungarica Series A Heavy Ion Physics · December 5, 2005
We discuss the hadron production in heavy ion collisions by the recombination and fragmentation model. We propose the elliptic flow as the useful tool for exploring final interactions for resonances, hadron structure for exotic particles and phase structur ...
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Journal articleEuropean Physical Journal C · August 1, 2005
The challenge of demonstrating that the matter produced in heavy ion collisions is a deconfined quark-gluon plasma as predicted by lattice QCD calculations is the challenge of measuring the number of thermodynamic degrees of freedom $\nu\sim\varepsilon/T∧4 ...
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Journal article · July 18, 2005
We calculate the wake induced in a hot QCD plasma by a fast parton in the framework of linear response theory. We discuss two scenarios: ($i$) a weakly coupled quark-gluon plasma described by hard-thermal loop perturbation theory and ($ii$) a strongly coup ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · July 7, 2005
We calculate the wake induced in a hot, dense QCD medium by a fast parton in the framework of linear response theory. We discuss two different scenarios: a weakly coupled quark-gluon plasma (pQGP) described by hard-thermal loop (HTL) perturbation theory an ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · July 7, 2005
Quark counting rules derived from recombination models agree well with data on hadron production at intermediate transverse momenta in relativistic heavy-ion collisions. They convey a simple picture of hadrons consisting only of valence quarks. We discuss ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · April 1, 2005
We discuss hadron production in relativistic heavy-ion collisions in the framework of the recombination and fragmentation model. We propose elliptic flow as a useful tool for exploring final interactions of resonances, the hadron structure of exotic partic ...
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Journal articlePhysical review letters · April 2005
We discuss different sources of hadron correlations in relativistic heavy ion collisions. We show that correlations among partons in a quasithermal medium can lead to the correlated emission of hadrons by quark recombination and argue that this mechanism o ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2005
We calculate the spectra of high-energy photons emitted in relativistic Au + Au collisions for various centralities and compare to data recently collected at the Relativistic Heavy Ion Collider by the PHENIX Collaboration. Our results for photons from prim ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2005
We explore possible ways of explaining the net charge event-by-event fluctuations in Au+Au collisions observed in experiments at the Relativistic Heavy Ion Collider within a quark recombination model. We estimate the number of quarks at recombination and t ...
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Journal articleCzech.J.Phys. · October 7, 2004
This is a review of the physics prospects for relativistic heavy ion collisions in the CERN Large Hadron Collider. The motivation for the study of superdense matter created in relativistic heavy ion collision is the prospect of observing a novel state of s ...
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Journal articleBiochemistry · October 2004
We have used time-resolved phosphorescence anisotropy (TPA) to probe rotational dynamics of the rabbit skeletal sarcoplasmic reticulum Ca-ATPase (SERCA), to test the hypothesis, generated from X-ray crystallography, that large-scale structural changes are ...
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Journal articlePhysical review letters · October 2004
We calculate the two-body correlation function of direct photons produced in central Au+Au collisions at the Relativistic Heavy-Ion Collider. Our calculation includes contributions from the early preequilibrium phase in which photons are produced via hard ...
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Journal articleActa Physica Hungarica Series A Heavy Ion Physics · August 23, 2004
We consider the Tsallis distribution as a source of the apparent slope of one-particle spectra in heavy-ion collisions and investigate the equation of state of this special kind of quark matter in the framework of non-extensive thermodynamics. We relate th ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · August 1, 2004
We present an analysis of the net baryon number rapidity distribution and of direct photon emission in the framework of the parton cascade model. ...
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Journal article · July 4, 2004
We discuss the anthropic principle and its implications for our existence and the physical laws which govern the universe. Several amazing coincidences which provide conditions necessary for creation of life suggest that the "laws of nature" are not unique ...
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Journal articleBiochemistry · July 2004
We used fluorescence resonance energy transfer (FRET) to detect and quantitate the interaction of the sarcoplasmic reticulum Ca-ATPase (SERCA) with phospholamban (PLB) in membranes. PLB inhibits SERCA only at submicromolar Ca. It has been proposed that rel ...
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Journal articleEuropean Physical Journal C · July 1, 2004
We give a brief overview of our current theoretical understanding of ultra-relativistic heavy ion collision and the properties of super-hot nuclear matter. We focus on several issues that have been discussed in connection with experimental results from the ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · January 1, 2004
We point out that exponential shape of transverse spectra can be obtained as the Fourier transform of the limiting distribution of randomly positioned partons with power law spectra given by pQCD, which actually realize Tsallis distributions. Such spectra ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · January 1, 2004
We show that hadron production in relativistic heavy-ion collisions at transverse momenta larger than 2 GeV/c can be explained by the competition of two different hadronization mechanisms. Above 5 GeV/c hadron production can be described by fragmentation o ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2004
We propose the measurement of the elliptic flow of hadron resonances at the Relativistic Heavy Ion Collider as a tool to probe the amount of hadronic final state interactions for resonances at intermediate and large transverse momenta. This can be achieved ...
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Journal article · November 18, 2003
This is the report of the NSAC Subcommittee on Nuclear Theory in response to a charge by the funding agencies to review and evaluate current NSF and DOE supported efforts in nuclear theory and identify strategic plans to ensure a strong U.S. nuclear theory ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · November 1, 2003
We consider the evolution of a parton system which is formed in the central region just after a relativistic heavy ion collision. The parton consists of mostly gluons, minijets, which are produced by elastic scattering between constituent partons of the co ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · October 1, 2003
We calculate the transverse momentum distribution of net quarks (quarks minus antiquarks) in Au+Au collisions at the Relativistic Heavy Ion Collider in the framework of the parton cascade model at two different rapidities. Parton re-scattering and fragment ...
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Journal articleEuropean journal of clinical investigation · August 2003
Aim/hypothesisIn the diagnosis of diabetic autonomic neuropathy (DAN) various autonomic tests are used. We took a novel statistical approach to find a combination of autonomic tests that best separates normal controls from patients with DAN.Me ...
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Journal articlePhysical review letters · August 2003
We calculate the net-baryon rapidity distribution in Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) in the framework of the parton cascade model (PCM). Parton rescattering and fragmentation leads to a substantial increase in the net-baryon ...
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Journal article · July 18, 2003
We demonstrate that the quantized U(1) lattice gauge theory in four Euclidean dimensions can be obtained as the long time limit of the corresponding classical U(1) gauge theory in 4+1 dimensions. The Planck constant hbar is related to the excitation energy ...
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Journal article · June 30, 2003
We calculate the entropy produced in the decoherence of a classical field configuration and compare it with the entropy of a fully thermalized state with the same energy. We find that decoherence alone accounts for a large fraction of the equilibrium entro ...
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Journal articleNuclear Physics A · June 30, 2003
We discuss characteristic experimental signatures related to the mechanism of DCC formation triggered by the chiral U(l) anomaly in relativistic heavy ion collisions. We predict an enhancement of the fraction of neutral pions compared with all pions in the ...
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Journal article · May 29, 2003
We review the idea of chaotic quantization, based on the dynamics of classical lattice gauge systems as well as on non-abelian plasma physics in the infrared limit. The basic conjecture between Planck constant and properties of the five dimensional classic ...
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Journal articlePhysical review letters · May 2003
We argue that the emission of hadrons with transverse momentum up to about 5 GeV/c in central relativistic heavy ion collisions is dominated by recombination, rather than fragmentation of partons. This mechanism provides a natural explanation for the obser ...
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Journal articlePhysical review letters · April 2003
We calculate the production of high-energy photons from Compton scattering and annihilation of a quark jet passing through a quark gluon plasma produced in a relativistic heavy ion collision. The contributions are large and reflect the momentum distributio ...
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Journal articleInternational Journal of Modern Physics E · April 1, 2003
This is a review of the parton cascade model (PCM) which provides a QCD-based description of nucleus-nucleus reactions at very high energy. The PCM describes the collision dynamics within the early and dense phase of the reaction in terms of the relativist ...
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Journal articleNuclear Physics A · March 10, 2003
We study the microscopic dynamics of quarks and gluons in relativistic heavy ion collisions in the framework of the Parton Cascade Model. We use lowest order perturbative QCD cross sections with fixed lower momentum cutoff p Tmin. We ...
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Journal articlePhysical review letters · February 2003
We calculate the production of high energy photons from Compton and annihilation processes as well as fragmentation off quarks in the parton cascade model. The multiple scattering of partons is seen to lead to a substantial production of high energy photon ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · January 9, 2003
We study the microscopic dynamics of quarks and gluons in relativistic heavy ion collisions in the framework of the Parton Cascade Model. We use lowest order perturbative QCD cross sections with fixed lower momentum cutoff PTmin. We c ...
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Journal articlePhysical Review Letters · January 1, 2003
We calculate the production of high-energy photons from Compton scattering and annihilation of a quark jet passing through a quark gluon plasma produced in a relativistic heavy ion collision. The contributions are large and reflect the momentum distributio ...
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Journal articlePhysical Review C - Nuclear Physics · January 1, 2003
We derive an analytical expression for the quenching factor in the strong quenching limit where the [Formula Presented] spectrum of hard partons is dominated by surface emission. We explore the phenomenological consequences of different scaling laws for th ...
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Journal articlePhysical Review C - Nuclear Physics · January 1, 2003
We discuss hadron production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC). We argue that hadrons at transverse momenta [Formula Presented] are formed by recombination of partons from the dense parton phase created in central collis ...
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Journal articlePhysical Review C - Nuclear Physics · 2003
We discuss hadron production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC). We argue that hadrons at transverse momenta P T<5 GeV are formed by recombination of partons from the dense parton phase created in central collisions at ...
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Journal articlePhysical Review Letters · 2003
The net-baryon multiplicity density distributions in Au + Au collisions were calculated at 130 and 200 GeV center-of-mass energy per nucleon pair. The parton cascade model predicted a net-baryon excess at midrapidity in Au + Au collisions, which was in agr ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2003
We derive an analytical expression for the quenching factor in the strong quenching limit where the pT spectrum of hard partons is dominated by surface emission. We explore the phenomenological consequences of different scaling laws for the ener ...
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Journal articlePhys. Rev. C, Rapid Communication · December 2002
We analyze the contribution of pQCD based semi-hard parton
(re)scattering to the reaction dynamics of relativistic
heavy-ion collisions at SPS and RHIC. While such processes
are able to account for the measured yield of high momentum
direct photons at SPS ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · October 1, 2002
We consider the evolution of a parton system which is formed at the central rapidity region just after an ultrarelativistic heavy-ion collision. The evolution of the system, which is composed of gluons, quarks and antiquarks, is described by relativistic B ...
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Journal articleNuclear Physics A · May 6, 2002
The use of statistical fluctuations as probes of the microscopic dynamics of hot and dense hadronic matter is reviewed. Critical fluctuations near the critical point of QCD matter are predicted to enhance fluctuations in pionic observables. Chemical fluctu ...
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Journal articlePhysical Review C - Nuclear Physics · January 1, 2002
We analyze the contribution of perturbative QCD based semihard parton (re)scattering to the reaction dynamics of relativistic heavy-ion collisions at SPS and RHIC. While such processes are able to account for the measured yield of high-momentum direct phot ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 2002
We discuss characteristic experimental signatures related to the formation of domains of disoriented chiral condensate triggered by the axial anomaly in relativistic heavy-ion collisions. We predict that the enhancement of the fraction of neutral pions com ...
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Journal articleFoundations of Physics Letters · October 1, 2001
We argue that the quantized non-Abelian gauge theory can be obtained as the infrared limit of the corresponding classical gauge theory in a higher dimension. We show how the transformation from classical to quantum field theory emerges, and calculate Planc ...
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Journal articleScience (New York, N.Y.) · December 2000
The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange quarks in generating nuclear magnetism. The measurement repo ...
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Journal articlePhysical review letters · September 2000
The size of the average fluctuations of net baryon number and electric charge in a finite volume of hadronic matter differs widely between the confined and deconfined phases. These differences may be exploited as indicators of the formation of a quark-gluo ...
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Journal articleNuclear Physics B · August 28, 2000
We calculate the Drell-Yan cross section, resolving the full kinematics of the lepton pair, at high transverse momentum for hadron nucleus collisions. We use the general framework of Luo, Qiu and Sterman to calculate double scattering contributions that ar ...
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Journal articlePhysical Review D - Particles, Fields, Gravitation and Cosmology · March 1, 2000
We investigate the relationship between the Lyapunov exponents of periodic trajectories, the average and fluctuations of Lyapunov exponents of ergodic trajectories, and the ergodic autocorrelation time for the two-dimensional hyperbola billiard. We then st ...
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Journal articleComputer Physics Communications · January 1, 2000
The Yang-Mills equations provide a classical mean field description of the non-Abelian soft glue field dynamics in heavy ion collisions at high energies. A C++ code for the numerical solution on a three-dimensional gauge lattice is presented. Non-perturbat ...
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Journal articlePhysical Review D · January 1, 2000
We investigate the relationship between the Lyapunov exponents of periodic trajectories, the average and fluctuations of Lyapunov exponents of ergodic trajectories, and the ergodic autocorrelation time for the twodimensional hyperbola billiard. We then stu ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · December 30, 1999
Different treatments for the inclusion of higher-order perturbative QCD corrections in parton based transport models of relativistic heavy-ion collisions are studied and their influence on experimental observables is investigated. At RHIC, particle multipl ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · November 1, 1999
We propose a novel formalism for simultaneously describing both the hard and soft parton dynamics in ultrarelativistic collisions of nuclei. The emission of gluons from the initially coherent parton configurations of the colliding nuclei and low-p1
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Journal articlePhysical Review Letters · January 1, 1999
We calculate the nuclear enhancement in the angular distribution of Drell-Yan pairs produced in proton-nucleus reactions. Nuclear effects are encoded in universal twist-4 parton correlation functions. We find that the Lam-Tung relation for the angular coef ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 1, 1999
The Yang-Mills equations provide a classical mean field description of gauge fields. In view of developing a coherent description of the formation of the quark gluon plasma in high energetic nucleus-nucleus collisions we study pure gauge field dynamics in ...
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Journal article · December 9, 1998
This paper discusses attempts to numerically compute the effects of hard thermal loops in non-abelian gauge theories at finite temperature by means of solutions of Heinz' transport equation for an ensemble of classical colored particles interacting with a ...
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Journal articleActa Physica Hungarica New Series Heavy Ion Physics · December 1, 1998
We examine the qualitative features of parton production through materialization in heavy-ion collisions within perturbative QCD, and estimate the magnitude of the resulting parton density created during the early stage of the collisions. The implications ...
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Journal article · October 1, 1998
We discuss the various physics aspects of hypothetical, coherent excitations of the pion field caused by spontaneously generated local distortions of the chiral order parameter. Such distortions, which may occur in the expansion of a hot fireball created i ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · September 23, 1998
We discuss the effect of the chiral anomaly as a possible mechanism for triggering the formation of domains of disoriented chiral condensate (DCC) in relativistic heavy ion collisions. The anomalous (Formula presented) coupling and the strong, Lorentz cont ...
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Journal articleNuclear Physics A · August 10, 1998
We give two reasons why we believe that non-central ultrarelativistic heavy ion collisions are the place to look for the disoriented chiral condensates (DCC). First, we argue that the most probable quench scenario for the formation of DCC requires non-cent ...
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Journal article · June 8, 1998
This is a review of theoretical attempts to describe production of heavy quark bound states in nucleus-nucleus collisions, in particular, the relative suppression of $J/ψ$ and $ψ'$ production observed in these reactions. The review begins with a survey of ...
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Journal articleNuclear Physics A · February 16, 1998
I survey the experimental signatures of a quark-gluon plasma in the light of present and future experiments. This includes a review of new theoretical results concerning the QCD equation of state and the formation of a dense parton plasma in high energy nu ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 1998
We calculate the cross sections for dissociation of [Formula Presented] by pions and ρ mesons within the framework of a meson exchange model. We find that these cross sections are small at center-of-mass energies less than 1 GeV above threshold, and that d ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 1998
We investigate the space-time structure of the classical gluon field produced in an ultrarelativistic collision between color charges. The classical solution which was computed previously in a perturbative approach is shown to become unstable on account of ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 1, 1998
We construct an extension of the standard Kogut-Susskind lattice model for classical [Formula Presented]-dimensional Yang-Mills theory, in which “classical particle” degrees of freedom are added. We argue that this will correctly reproduce the “hard therma ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · September 18, 1997
We propose a formulation of the long-distance dynamics of gauge theories at finite temperature on a lattice in Minkowski space, including the effects of hard thermal loops on the dynamics of the long wavelength modes. Our approach is based on the dual clas ...
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Journal articlePhysical Review Letters · March 31, 1997
We discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using massless scalar electrodynamics as an example, we show how the ra ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · March 20, 1997
The chemical equilibration of the parton distribution in collisions of two heavy nuclei at the CERN Large Hadron Collider is investigated. Initial conditions are obtained from a self-screened parton cascade calculation. The onset of transverse expansion of ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 1997
We investigate the chemical equilibration of the parton distributions in collisions of two heavy nuclei. We use initial conditions obtained from a self-screened parton cascade calculation and, for comparison, from the HIJING model. We consider a one-dimens ...
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Journal articleFoundations of Physics · January 1, 1997
We discuss the intimate connection between the chaotic dynamics of a classical field theory and the instability of the one-loop effective action of the associated quantum field theory. Using the example of massless scalar electrodynamics, we show how the r ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 1, 1997
We investigate thermalization processes occurring at different time scales in the Yang-Mills-Higgs system at high temperatures. We determine the largest Lyapunov exponent associated with the gauge fields and verify its relation to the perturbatively calcul ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 1, 1997
We discuss the classical limit for the long-distance (“soft”) modes of a quantum field when the hard modes of the field are in thermal equilibrium. We address the question of the correct semiclassical dynamics when a momentum cutoff [Formula presented] is ...
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Journal articlePhysical Review C Nuclear Physics · January 1, 1997
We explore the correspondence between classical gluon radiation and quantum radiation in a coherent state for gluons produced in ultrarelativistic nuclear collisions. The expectation value of the invariant momentum distribution of gluons in the coherent st ...
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Journal articleActa Physica Hungarica New Series Heavy Ion Physics · December 1, 1996
I review the arguments for considering the strange quark as a probe of changes in the QCD vacuum, and of the formation of a quark-gluon plasma, in particular. I survey existing data showing enhanced production of strange hadrons in relativistic heavy ion c ...
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Journal article · August 8, 1996
The high density of scattered partons predicted in nuclear collisions at very high energy makes color screening effects significant. We explain how these screening mechanisms may suppress nonperturbative, soft QCD processes, permitting a consistent calcula ...
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Journal article · July 5, 1996
Following a recent suggestion by Nielsen, Rugh, and Rugh, we study the energy scaling of the maximal Lyapunov exponent of classical Hamiltonian SU(2) lattice gauge theory. It is shown that the conjectured scaling behavior $λ_0\sim E^{1/4}$ at small energie ...
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Journal article · June 28, 1996
I review the current status of lattice Monte-Carlo computations of the equation of state of QCD, our current understanding of the thermalization process at collider energies, and two new theoretical developments, one pertaining to the ab-initio calculation ...
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Journal articlePhysics Letters Section B Nuclear Elementary Particle and High Energy Physics · June 6, 1996
We discuss the effect of strong electromagnetic fields on chiral orientation in the framework of the linear σ model. Based on lessons we learn from computation of the effective potential at one loop, we argue that the chiral U(1) anomaly dominates chiral d ...
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Journal articlePhysical Review D Particles Fields Gravitation and Cosmology · January 1, 1996
We present numerical simulations of colliding wave packets in spontaneously broken SU(2) Yang-Mills-Higgs theory. Compared with pure Yang-Mills theory, introducing the Higgs field leads to new aspects in the dynamics of the system. The evolution of the gau ...
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Journal articlePhysics Report · January 1, 1996
The transition from reversible microdynamics to irreversible transport can be studied very efficiently and systematically with the help of the so-called projection method. After a concise introduction to that method we illustrate its power by using it to a ...
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Journal articleAnnual Review of Nuclear and Particle Science · January 1, 1996
We provide an overview of the present understanding of the transition from hadrons to a quark-gluon plasma, its signatures, and the experimental results so far. We discuss results of numerical simulations of the lattice gauge theory and critically evaluate ...
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Journal articleReports on Progress in Physics · December 1, 1995
This is a critical review of the various observables that have been proposed to signal the change from dense hadronic matter to a quark-gluon plasma at high temperature or baryon density. I discuss current models of quark-gluon plasma formation in relativi ...
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Journal articlePhysics Letters B · November 16, 1995
We study the conversion of the latent heat of a supercooled quark-gluon plasma into excitations of the pion field. Supercooling is predicted to occur in the late stages of the evolution of a quark-gluon plasma produced in energetic heavy-ion collisions, if ...
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Journal articlePhysics Letters B · November 9, 1995
We argue on a basis of a simple few modes model of SU(2) Yang-Mills theory that the color off-diagonal coupling of the soft plasmon to hard thermal excitations of the gauge field drives the collective plasma oscillations into chaotic motion despite the pre ...
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Journal article · February 15, 1995
We review the accomplishments of nuclear theory during the past five years and identify the future challenges and research opportunities. [Final, substantially revised version of the nuclear theory white paper] ...
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Journal articlePhysical Review D · January 1, 1995
We estimate the cross section for quasielastic double pion exchange in high energy proton-proton collisions. Total and elastic ππ cross sections are calculated in an equivalent pion approximation, with pion-baryon vertices taken from chiral perturbation th ...
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Journal article · August 14, 1994
I review recent progress in our understanding of the basis of statistical models for hadronic reactions and of the mechanisms of thermalization in nonabelian gauge theories. (Invited talk given at the NATO Advanced Research Workshop on Hot Hadronic Matter: ...
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Journal articlePhysics Letters B · June 23, 1994
Relativistic heavy ion collisions can generate metastable domains in which the chiral condensate is disoriented. Nucleussizeddomains can yield measurable fluctuations in the number of neutral and charged pions. We propose a scenario in whichdomains are "an ...
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Journal articleNuclear Physics Section A · February 28, 1994
Applying a variational method to a gaussian wave ansatz, we have derived a set of semi-classical evolution equations for SU(2) lattice gauge fields, which take the classical form in the limit of a vanishing width of the gaussian wave packet. These equation ...
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Journal articleNuclear Physics Section A · January 3, 1994
Initial parton scatterings produce a hot and dilute gluonic gas in high energy nuclear collisions. Pre-equilibrium gluon rescatterings are shown to have significant contributions to the charm production. In contrast to the gluon shadowing effect in the ini ...
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Journal articleNuclear Physics Section A · January 3, 1994
The processes leading to phase space equilibration of parton distributions in ultrarelativistic heavy ion collisions are investigated. A set of rate equations describing the chemical equilibration of quarks and gluons based on perturbative QCD including me ...
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Journal articlePhysical Review D · January 1, 1994
We introduce the Wigner functional representing a quantum field in terms of the field amplitudes and their conjugate momenta. The equation of motion for the functional of a scalar field points out the relevance of solutions of the classical field equations ...
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Journal articlePhysical Review C · January 1, 1994
We report a measurement of the asymmetry in spin-dependent quasielastic scattering of longitudinally polarized electrons from a polarized He3 target. The neutron magnetic form factor GMn has been extracted from the measured asymmetry based on recent PWIA c ...
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Journal articlePhysics Letters B · December 16, 1993
The recently introduced κ-Poincar e ́-Dirac equation is gauged to treat the κ-Dirac-Coulomb problem. For the resulting equation, we prove that the perturbation to first order in the quantum group parameter vanishes identically. The second order perturbation ...
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Journal articlePhysics Letters B · October 21, 1993
Recently it was pointed out that coherent or condensated states of pions may account for the explanation of the Centauro events observed in cosmic ray showers. We argue that an occurence of condensed pions requires that the system evolves far out of therma ...
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Journal articleNuclear Physics Section A · September 6, 1993
We develop a method to calculate the density of magnetic monopoles in nonabelian gauge theories at finite temperature in the dilute gas approximation in the semiclassical limit. This quantity is related to the inverse magnetic screening length for which we ...
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Journal articlePhysical Review A · January 1, 1993
Using relativistic Green's-function techniques we examined single-electron excitations from the occupied Dirac sea in the presence of strong external fields. The energies of these excited states are determined taking into account the electron-electron inte ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · December 1, 1992
The authors calculate the inclusive parton-parton cross section in p+p and p+p collisions in the framework of perturbative QCD and snow that the measured non-diffractive cross section requires a transverse momentum cut-off p Tmin of s ...
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Journal articleNuclear Physics Section A · July 20, 1992
I review the various observables that have been proposed as signals for the change in the structure of dense hadronic matter, when it becomes quark-gluon plasma at high temperature, or quark matter at high baryon density. I also discuss the inherent ambigu ...
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Journal articleNuclear Physics Section A · July 20, 1992
We present a QCD based relativistic kinetic model for high energy nuclear colisions, which is inspired by the parton picture of hadronic interactions. The nuclear dynamics is traced back to the microscopic level of quark and gluon interactions in the frame ...
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Journal articleNuclear Physics Section B · February 3, 1992
We present a fully relativistic space-time approach for the simulation of highly-energetic nucleus-nucleus collisions. The model incorporates the idea of the factorization of short-range parton-parton interactions and the hadronization process. The nuclear ...
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Journal articlePhysical Review C · January 1, 1992
Nuclear attenuation of the leading (xf>0) hadron and the nuclear enhancement of target fragmentation (xf<0) hadrons in lepton-nucleus reactions are calculated via a (3+1)-dimensional string-parton model. A (1+1)-dimensional string model is used to investig ...
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Journal articlePhysical Review Letters · January 1, 1992
We show that higher-order vacuum polarization would contribute a measurable net charge to atoms, if the charges of electrons and positrons do not balance precisely. We obtain the limit Qe+Qē<10-18e for the sum of the charges of electron and positron. This ...
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Journal articlePhysical Review Letters · January 1, 1992
We present numerical evidence that the real-time Hamiltonian dynamics of SU(2) gauge theory on a spatial lattice exhibits deterministic chaos in the semiclassical limit. We determine the largest Lyapunov exponent of the gauge field as a function of energy ...
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Journal articleNuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · December 1991Full textCite
Journal articleReports on Progress in Physics · December 1, 1991
Electron-positron scattering provides a model-independent test for the existence of neutral particles coupling to the e+e- field. The authors review the effects of possible particle resonances X0 in the energy range between ...
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Journal articleNuclear Physics Section A · January 1, 1991
Higgs boson production by coherent double-pomeron exchange in peripheral nuclear collisions at energies of several TeV per nucleon is calculated. It is shown that a trigger on quasi-elastic nuclear collisions strongly suppresses the cross section. The anal ...
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Journal articlePhysical Review A · January 1, 1991
We consider the contribution of nuclear polarization to the Lamb shift of K- and L-shell electrons in heavy atoms and quasiatoms. Our formal approach is based on the concept of effective photon propagators with nuclear-polarization insertions treating effe ...
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Journal articlePhysical Review Letters · January 1, 1991
In order to investigate the coupling between collective flow of nucleons and pions in hot pion-dominated hadronic matter, we calculate the pion-nucleon drag coefficient in linearized transport theory. We find that the characteristic time for flow equalizat ...
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Journal articleNuclear Physics Section A · January 1, 1991
The idea of producing neutral particles via fusion of virtual photons accompanying ultra-relaitivistic heavy ions is reviewed. In particular, the possibility that such a mechanism could provide a method for producing and detecting intermediate mass Higgs b ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · December 1, 1990
Heavy ions with energies of some TeV per nucleon can be considered as carriers of intense photon fields. In peripheral collisions elementary particles with masses up to a few 100 GeV can be produced via two-photon processes. The authors evaluate total cros ...
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Journal articleJournal of Physics B Atomic Molecular and Optical Physics · September 28, 1990
Ag I autoionizing levels were populated by a combination of discharge and laser excitation. Twenty-six of the observed lines are assigned to dipole transitions to the Ag I 4d95snl (nl=5p, 6s, 5d, 7s, 6d) configurations. An additional 37 unclassi ...
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Journal articlePhysics Letters B · September 6, 1990
We have studied the pair creation rate in a cylindrical region of space with a homogeneous electric field parallel to the cylinder axis. MIT boundary conditions on the surface of the cylinder are imposed. The wave functions of the created particles are cal ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1990
The rates for X° creation by photons and electrons channeling along a crystal axis are estimated. The process is found to depend strongly on the parameters of the crystal fields. Promising X° production rates can therefore be obtained ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1990
We describe the (α n μ)-(d t μ) continuum above and below the d+(t μ)1s threshold using the R-matrix formalism. The continuum is explicitly constructed in an adiabatic approximation, and the asymptotic phase shifts and amplitudes in all channels ...
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Journal articleZeitschrift Fur Physik C Particles and Fields · June 1, 1990
We present a phenomenological model for meson-glueball mixing and apply it to the mixing of the pseudoscalar mesons η and η′ with the ι(1440)-particle as the prime candidate for a 0-+-glueball. Using the MIT bag model framework, our model incorp ...
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Journal articlePhysics Letters B · April 26, 1990
The transverse momentum distribution of (anti) quarks created in the chromo-electric field of an infinitely long hadronic flux tube is derived. The effects of the finite radius of the hadronic strings on their fragmentation are studied simulating e+
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Journal articleZeitschrift Fur Physik C Particles and Fields · March 1, 1990
Bose-Einstein correlation of identical pions in e+e- annihilation at {Mathematical expression} GeV c.m. energy is studied within the framework of a dynamic string model of hadrons. It is shown that taking Fourier transform of the meas ...
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Journal articleComputer Physics Communications · January 1, 1990
The introduction of a μ- particle into a mixture of hydrogen isotopes brings about a repetitive cycle of processes leading to nuclear fusion and the release of energy. Sticking is one of the critical processes limiting the number of fusions indu ...
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Journal articleJournal of Mathematical Physics · January 1, 1990
A model for composite systems consisting of fermions with internal degrees of freedom interacting via intermediate vector bosons (IVB) is constructed. Highly localized, low-mass bound states are found in the Hartree-Fock approximation. The dependence of th ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · December 1, 1989
The authors discuss an extended particle structure whose decay into e +e- may be the source of the correlated electron-positron coincidences in heavy-ion collisions measured at GSI. The general properties of the particle, like its exc ...
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Journal articleZeitschrift Fur Physik D Atoms Molecules and Clusters · December 1, 1989
The elastic scattering of an electron by a hydrogenic ion of charge (Z-1) is investigated. For scattering energies Ekin in the eV region, where the Bohr-Sommerfeld parameter y is large compared to one, the cross section for spin exchange of the ...
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Journal articlePhysics Letters B · March 16, 1989
We point out the possible role of neutral strange particles (Λ, KoS) as probes for the size of a baryon-rich fireball formed in relativistic nuclear collisions. A striking difference in the size parameters determined by the hyperons o ...
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Journal articlePhysical Review A · January 1, 1989
The energy shift of the 1s1/2 state in U92238 due to virtual excitation of nuclear rotational modes is shown to be a considerable correction for atomic high-precision experiments. In contrast to this, nuclear polarization effects are of minor importance fo ...
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Journal articleJournal of Physics G Nuclear and Particle Physics · January 1, 1989
Nuclear beams with energies of several TeV per nucleon are considered as carriers of intense fields of photons in the energy range up to 100 GeV. Cross sections for intermediate boson and Higgs production by two-photon collisions are predicted to be in the ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 1989
We comprehensively reanalyze and search for the density dependence of the effective muon alpha sticking fraction ωsff observed experimentally in muon catalyzed deuterium-tritium fusion. In our work particular emphasis has been put on ...
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Journal articlePhysical Review A · January 1, 1989
Parity mixing of electron states should be extremely strong for heliumlike uranium. We calculate its size and discuss whether it could be determined experimentally. We analyze one specific scheme for such an experiment. The required laser intensities for t ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1988
The creation of a hypothetical many-electron-positron bound system was suggested as a possible source of the correlated peaks observed in the e + and e- spectra of various heavy-ion collisions. A new electron-electron interaction was ...
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Journal articleZeitschrift Fur Physik D Atoms Molecules and Clusters · December 1, 1988
In recent experiments at least two structures have been detected in positron spectra from subcritical (total charge Z ≦ 174) heavy-ion collisions at bombarding energies ELab=5.7-5.9 MeV/n. The origin of these structures is unexplained up to now. ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1988
We have studied photon production in heavy-ion collisions at intermediate energies in the Molecular Dynamics approach, where the radiation amplitudes have been derived from the many-body dynamics in the classical bremsstrahlung formalism. This concept allo ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1988
We calculate δ-electron and positron distributions resulting from heavy ion collisions under consideration of a sequential fission in the outgoing channel. The resulting spectra are found to be only weakly sensitive to the underlying dynamics of the fissio ...
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Journal articleAnnals of Physics · August 1, 1988
We give general arguments that no narrow quasi-bound e+ e- state can exist above 2me. We extend the virial theorem of QED to quasi-bound states and show that corrections due to renormalization and due to the fact that a res ...
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Journal articlePhysical Review A · January 1, 1988
Positron creation in crossed-beam collisions of high-energy, fully stripped heavy ions is investigated within the coupled-channel formalism. In comparison with fixed-target collisions of highly stripped heavy-ion projectiles positron production probabiliti ...
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Journal articlePhysical Review A · January 1, 1988
We investigate the influence of additional nonlinear terms in the Dirac Lagrangian on strongly bound electron states in heavy and superheavy atoms. Upper bounds for the coupling constants are deduced by comparison with precision spectroscopy data in QED. W ...
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Journal articleNuclear Physics Section A · January 1, 1988
We investigate possible consequences of strangeness formation in heavy ion reactions at different excitation energies. First of all we study ground state properties of multi-Λ hypernuclei. They seem to have strongly enhanced interaction radii and could be ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · December 1, 1987
We discuss, on a phenomenological level, the possible appearance of resonances in e++e- scattering at energies in the MeV region. The expected resonance cross section and angular distribution are examined. The observability depends cr ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1987
A new method to describe the presence of multi-particle clusters in the ground state (vacuum) of a many-body system is presented. It relies on a unitary transformation in Fock space and can be used to investigate alpha -clustering in nuclei as well as clus ...
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Journal articlePhysics Letters B · November 19, 1987
The scattering matrix describing the electron-positron excitation during a heavy-ion collision is discussed. It is shown that spontaneous positron emission in the presence of a long nuclear delay time precisely corresponds to the formal resonance condition ...
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Journal articlePhysica Scripta · November 1, 1987
Characteristic features of positron creation in collisions of very heavy ions are depicted. First continuum solutions of the two-centre Dirac equation are presented. Calculated e+-production probabilities are compared with experimental data. The ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1987
Based on a classical dynamical model of nuclear motion with a velocity dependent friction force we calculate pionic and electromagnetic bremsstrahlung emitted in heavy ion collisions with bombarding energies between 20 and 84 MeV/n. For arbitrary projectil ...
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Journal articleZeitschrift Fur Physik D Atoms Molecules and Clusters · June 1, 1987
Theoretical results for the impact parameter dependence of the A20 alignment parameter are compared with experimental data. The calculations have been performed within a coupled channel formalism, using relativistic atomic wave functions as basi ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · March 1, 1987
We investigate the strength of angular correlations between coincident electron-positron pairs produced in Pb + Pb collisions at 5.7 MeV/u. The angular correlations are predicted to be observable at electron energies above 200 keV, almost independent of po ...
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Journal articlePhysics Letters B · January 15, 1987
It was proposed in a former paper [A. Schäfer, B. Müller and W. Greiner, Phys. Lett. B 149 (1984) 455] that in strong fields the VEV of a Higgs field can become space and time dependent and that the Goldstone boson might become visible. As an example the G ...
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Journal articleNuclear Physics Section A · January 5, 1987
The prospects of detecting the formation of a quark-gluon plasma in nuclear collisions at very high energy are reviewed. Predictions that the strange versus nonstrange antibaryon ratio is a good signal in the baryon-"rich" region are confirmed. The usefuln ...
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Journal articlePhysica A Statistical Mechanics and Its Applications · January 1, 1987
We derive an integral representation for the temperature corrections to the Casimir effect between perfectly conducting parallel plates placed in the electromagnetic field for arbitrary dimension. The representation has the advantage that dependence upon t ...
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Journal articlePhysica B C · January 1, 1987
We present theoretical positron- and δ-electron spectra for the sub-critical systems Ta + Th (Ztot = 163) and U + Au (Ztot = 171) as a function of impact parameter b and laboratory angle θL. For the system Ta + Th in additi ...
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Journal articleAnnals of Physics · January 1, 1987
We consider the coupling between collective and intrinsic degrees of freedom of a many-dimensional quantum system. We give a criterion for the validity of the adiabatic approximation in tunneling processes and derive an equation for the "lag" of the intrin ...
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Journal articlePhysica A Statistical Mechanics and Its Applications · January 1, 1987
We review the relativistic Fermi gas in an inhomogeneous velocity field and calculate components of the current vector and the energy-momentum tensor in a comoving frame. We derive quantum corrections to the classical distribution function in the framework ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1986
The authors suggest that a system containing several electron-positron pairs (an 'e+e- droplet') could be highly localised and tightly bound if there exists a many-body force of short range acting between leptons. Such a state could h ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · December 1, 1986
The formation and evolution of strange quarks in quark gluon plasma is studied assuming perturbative QCD and qualitative models of plasma phase expansion. Chemical equilibrium abundance characteristic of the hottest and densest phase of nuclear collisions ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1986
U-U collisions at energies near the Coulomb barrier are discussed. A quantum mechanical treatment of nuclear motion including the influence of quasibound states in a pocket of the scattering potential is developed. Positron emission probabilities are calcu ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1986
Dynamical and spontaneous positron emission are investigated for heavy-ion collisions with long time delay using a semiclassical description. Numerical results and analytical expressions for the characteristic quantities of the resulting spontaneous positr ...
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Journal articleZeitschrift Fur Physik A Atomic Nuclei · September 1, 1986
Following up our earlier work and also stimulated by recent experimental results on positron production in heavy ion collisions we investigate various mechanisms for the production of a light, previously unknown particle in such collisions. As more convent ...
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Journal articlePhysics Letters B · March 27, 1986
A new scaling law is presented for the emission of electrons in intermediate-energy heavy ion collisions. An improved formula is obtained which correctly describes electron emission also in the limit of very short nuclear stopping times τ. In this limit th ...
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Journal articleZeitschrift Fur Physik D Atoms Molecules and Clusters · March 1, 1986
Molecular orbital K x-rays emitted during Pb+Pb collisions are investigated. Two results are presented: A slight filling up of the minimum observed in the differential radiation cross-section is given by radiative transitions from the M-shell to the L-shel ...
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Journal articleAnnals of Physics · January 1, 1986
We calculate the metric of the orbit space in the free Yang-Mills theory and in scalar electrodynamics. From this metric we derive the curvature of the orbit space. We examine singular points where the curvature is ill defined. Finally we discuss the relat ...
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Journal articlePhysics Reports · January 1, 1986
This report gives an introduction to the Casimir effect in quantum field theory and its applications. The interaction between the vacuum of a quantized field and an external boundary or a classical external field is investigated laying particular emphasis ...
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Journal articlePhysical Review C · January 1, 1986
We discuss the possibility that the line structure observed in the spectrum of the positrons produced in heavy ion collisions is due to the decay of a new neutral elementary particle. We argue that this can be ruled out unless one is willing to accept fine ...
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Journal articlePhysics Reports · January 1, 1986
Abundances of strange antibaryons formed in nuclear collisions at above 10 GeV/A are considered as a most accessible diagnostic tool for the study of the possible formation and physical properties of the quark-gluon plasma phase of hadronic matter. In this ...
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Journal articlePhysical Review D · January 1, 1986
We calculate the cross section for the production of a hypothetical light neutral pseudoscalar particle in heavy-ion collisions due to the two-photon process. For an inverse coupling strength f in the 100-GeV range we predict a cross section of 10-14 fm2 f ...
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Journal articlePhysics Letters B · December 12, 1985
Loss of muons due to capture (sticking) by the α-particle formed in a muon catalysed D-T fusion process driven by the intermediate nuclear resonant state in 5He( 3 2+) is investigated. Depending on the properties of the resonant doorw ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1985
We present a relativistic Hartree-Fock calculation of the parity violating E1-matrixelement of the 6 s↔7 s transition in cesium. Our result E1= -8.4·10-12iea0 for sin2θw = 0.22 is in good agreement with the exper ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1985
We show that emission of high-energy electrons and photons in nuclear collisions at intermediate energies is sensitive to the space-time evolution of the reaction. The electron and photon spectra measure related but complementary quantities connected with ...
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Journal articleNuclear Inst and Methods in Physics Research A · November 1, 1985
A coupled channel formalism is presented, using relativistic basis states of the target atom. Screening effects are incorporated by means of an effective potential of the Hartree-Fock-Slater type. Relativistic wave packets are employed for the description ...
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Journal articleIl Nuovo Cimento A · October 1, 1985
The field of a magnetic pointlike monopole acts in a similar way on a charged Dirac particle as the field of a very strong electric point charge. To explore this parallel we construct a field solution for an extended magnetic-charge distribution. In contra ...
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Journal articleNuclear Inst and Methods in Physics Research B · May 15, 1985
Theoretical results for the δ-electron distribution and positron emission in superheavy systems are compared with recent experimental data. Special emphasis is laid on atomic excitations in deep inelastic nuclear collisions. It is demonstrated that the stu ...
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Journal articleNuclear Physics Section A · March 18, 1985
A hypothetical quark-gluon plasma is described as a large bag, filled with quarks, antiquarks, and gluons, of radius R ∼ 2-6 fm and temperature T ∼ 100-250 MeV. We consider the cooling of this plasma through pion emission at the bag surface in a chiral-mod ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · March 1, 1985
In a specially designed collision chamber, H atoms produced by a microwave discharge were excited into the 2 p state by impact of Ar+ ions in a beam. A degree of dissociation up to η=94% was measured at the exit of the microwave source, although ...
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Journal articleNuclear Inst and Methods in Physics Research B · January 1, 1985
Distinct peak structures have been observed in spectra of positrons emitted in collisions of very heavy ions such as U-Th, U-U, Th-Cm and U-Cm. Characteristic features of these structures are discussed and confronted with our theoretical results. It is arg ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 1985
The structure of the vacuum has become of general importance in modern physics. In this context the vacuum of quantum electrodynamics plays a special role because it changes drastically in strong external electric fields and these changes can be followed i ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 1985
We investigate the spectra of electrons which are emitted during heavy ion collisions, traditionally denoted as δ-electrons. The slope in the kinetic energy distribution of ejected δ-electrons provides a finger-print of the occuring delay and deceleration ...
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Journal articlePhysics Letters B · December 27, 1984
We analyse the properties of spontaneous symmetry breaking in the presence of external sources, concentrating on the question whether these sources can lead to a change of the vacuum expectation value of the Higgs field. We discuss in particular how the me ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1984
The single-particle spectrum of a light quark moving in the field generated by a heavy quark-antiquark pair placed at the foci of an ellipsoidal bag is calculated in a variational approach. Residual interactions due to gluon exchange are accounted for in t ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · December 1, 1984
The authors present calculations of electron excitation rates in heavy-ion collisions, in which the electron-electron interaction is treated within a relativistic self-consistent field approach. In comparison with earlier calculations neglecting electron s ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · October 1, 1984
From a quantum mechanical model for quasielastic nuclear scattering, involving a pocket in the internuclear potential, we derive a distribution of nuclear delay times. We show that coherent excitation of states in a rotational band of nuclear resonances le ...
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Journal articlePhysics Letters B · August 16, 1984
The electric and magnetic polarizabilities of the proton and neutron are calculated in the framework of the MIT bag model. Neglecting vacuum-polarization we get αp = αn = 10.8 × 10-4 fm3, βp = 2.3 × 10 ...
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Journal articleAnnals of Physics · January 1, 1984
From a quantum mechanical model for quasielastic nuclear scattering, employing a pocket in the internuclear potential at close distances, a distribution of nuclear delay times is derived. The influence of this time structure on atomic excitation spectra is ...
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Journal articlePhysical Review C · January 1, 1984
Atomic excitations are used to obtain information on the course of a nuclear reaction. Employing a semiclassical picture we calculate the emission of δ electrons and positrons in deep inelastic nuclear reactions for the example of U+U collisions incorporat ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1983
The authors have solved the quark confinement boundary-value problem of the MIT bag model numerically for axially deformed bag shapes. As first results they present a Nilsson-type level diagram for quarks confined in a deformed cavity. Minimising the baryo ...
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Journal articleZeitschrift Fur Physik C Particles and Fields · December 1, 1983
With the string picture in mind, we study quark bags of a simple fixed geometry: cylindrical. It is shown that the Dirac boundary value problem {Mathematical expression} of the M.I.T. bag model has no solutions, if this quark confinement condition is appli ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1983
During collisions of heavy nuclei with a combined charge Z≳160 the electronic 1 s-state is deeply bound due to the strong Coulomb field, for Z≧173 it even enters as a resonance the lower continuum of the Dirac-Hamiltonian. In pure Rutherford scattering no ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · September 1, 1983
In superheavy quasimolecules the number of created 1 sσ-vacancies per collisions P1sσ can be evaluated approximately by a simple scaling law. This analytical relation correctly reproduces the measured dependence of P1sσ on the impact ...
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Journal articlePhysics Letters A · March 7, 1983
Molecular orbital K X-rays emitted during Pb + Pb collisions are investigated assuming nuclear contact with sticking times of 10-19 s and 3 × 10-20 s, respectively. A peak in the differential radiation spectrum near the united-atom Kα ...
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Journal articleZeitschrift Fur Physik C Particles and Fields · March 1, 1983
We describe the fission of heavy quarkonia as the decay of the bag vacuum state by spontaneous creation of a light quark-antiquark pair due to super-critical colour-electric fields. In the adiabatic approximation the heavy quarks are reduced to two point c ...
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Journal articlePhysical Review Letters · January 1, 1983
A new spontaneous-symmetry-breaking mechanism is formulated for SU(3), which is used to describe the formation of bags around quarks. The Higgs field is replaced by the scalar product of two colored fermion fields. This model gives mass only to one gluon ( ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · January 1, 1983
The energy distribution of positrons emitted in quasimolecular collisions of Uranium on Uranium and Uranium on Curium has been measured by several groups. Peak structures in the positron spectra were observed. We discuss the possibility that these structur ...
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Journal articleAnnals of Physics · January 1, 1983
A general theory is formulated of electron-positron excitations in heavy ion collisions with nuclear contact, treating the nuclear relative motion quantum mechanically. A set of coupled channel equations for the electronic occupation amplitudes is derived, ...
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Journal articlePhysical Review A · January 1, 1983
Excitations of the atomic shell in heavy-ion collisions are influenced by the presence of a nuclear reaction. In the present Rapid Communication we point out the equivalence between a semiclassical description based on the nuclear autocorrelation function ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1982
Presents approximate solutions of the MIT bag model for quarks in cylindrical bags. For a cylindrical bag surface it is found that Dirac's equation does not admit solutions corresponding to the linear boundary condition in psi = psi . It admits, neverthele ...
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Journal articlePhysics Letters B · October 14, 1982
Internal symmetry influences the form of quantum spectra as well as the abundance of particles emitted by a thermal source. Isospin conservation in proton-antiproton annihilation is used to quantitatively illustrate the influence of these phenomena on mean ...
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Journal articlePhysics Reports · January 1, 1982
We consider various gauge fields coupled to the free Dirac equation according to symmetry principles. The gauge fields are treated as classical, unquantized fields. Sufficiently strong time-independent fields may give rise to spontaneous particle creation ...
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Journal articlePhysical Review Letters · January 1, 1982
Rates are calculated for the processes gg→ss̄ and uū,dd̄→ss̄ in highly excited quarkgluon plasma. For temperature T>~160 MeV the strangeness abundance saturates during the lifetime (∼10-23 sec) of the plasma created in high-energy nuclear collisions. The chem ...
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Journal articlePhysical Review Letters · January 1, 1982
The energy shift of K electrons in heavy atoms due to the self-energy correction has been calculated. This process is treated to all orders in Zα, where Z denotes the nuclear charge. For the superheavy system Z=170, where the K-shell binding energy reaches ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · September 1, 1981
In the strong Coulomb field of a nucleus or quasimolecule with Z≳172 a change of the QED vacuum has been predicted, signalled by the spontaneous emission of positrons if holes in the K-shell are available. The dynamical semiclassical theory of positron exc ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · September 1, 1981
We present a detailed comparison of theoretical results on 1 sσ-ionization probabilities and δ-electron production rates with recent experimental data. The investigations are restricted to collisions of very heavy ions with (Z1+Z2)α≳1 ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · June 1, 1981
We investigate the behaviour of the vacuum charge around a supercritical nucleus with Z>137 in dependence on the nuclear radius. The screening effects are considered in a quasiclassical approximation. We show that in the point nucleus limit the nuclear cha ...
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Journal articlePhysics Letters B · April 30, 1981
We calculate the free energy for a gauge field at finite temperature in the presence of a constant gauge magnetic field in the one-loop approximation, omitting unstable modes. The effect of finite temperature on the approximate "true" Savvidy ground state ...
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Journal articlePhysical Review A · January 1, 1981
Collisions of very heavy ions at energies close to the Coulomb barrier are discussed as a unique tool to study the behavior of the electron-positron field in the presence of strong external electromagnetic fields. To calculate the excitation processes indu ...
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Journal articlePhysical Review A · January 1, 1981
The origin and importance of electron-translation effects within a molecular description of electronic excitations in heavy-ion collisions is investigated. First, a fully consistent quantum-mechanical description of the scattering process is developed; the ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1980
We investigate the dependence of inner shell vacancy production on interaction time T in deep inelastic nuclear reactions. Coupled channel calculations for Xe-Pb, Pb-Pb, and U-U collisions are presented. In the heaviest system strong interference minima fo ...
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Journal articlePhysics Letters B · June 16, 1980
We investigate the dependence of pion bremsstrahlung on the deceleration of the nuclei in relativistic heavy ion collisions. The vicinity of an abnormal phase in nuclear matter can lead - owing to critical N-N scattering - to faster deceleration or decreas ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · June 1, 1980
We calculate the ionization probability of the quasimolecular 1 sσ-state in collisions of very heavy ions with (Z1+Z2) α≳1. Multistep excitation processes between bound and continuum states are investigated. Due to the multistep proce ...
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Journal articleZeitschrift Fur Physik B Condensed Matter and Quanta · January 1, 1980
Heavy ion induced density fluctuations in the electron plasma of solids known as wakes show the characteristic features of Mach-shock waves. We propose a method to detect the electron wake in solid state materials by measuring the angular distribution of e ...
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Journal articlePhysical Review C · January 1, 1980
A method for the description of spin-isospin phase transitions in nuclear matter is developed. It allows a complete description of the pion condensation phase transition in the framework of the Landau-Migdal Fermi liquid theory. The equation of the order p ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 1980
Quantum Electrodynamics of strong external fields is discussed in the context of atomic physics. For sufficiently large electromagnetic coupling constant Zα bound states can approach and even join the antiparticle continuum of the Dirac equation. The resul ...
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Journal articleProgress in Particle and Nuclear Physics · January 1, 1980
Collisions of very heavy ions are discussed as a means to investigate quantum electrodynamics in the presence of strong external fields. The action of the combined Coulomb field of the closely approaching nuclei leads to strong binding of the inner electro ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · December 1, 1979
In collisions of very heavy ions (Z1+Z2 greater than 173) the binding energy of the quasimolecular 1s sigma state may exceed twice the electron rest mass. The critical internuclear separation is calculated within the relativistic Hart ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · December 1, 1979
Transition probabilities for inner-shell electrons during the formation of quasi-molecular systems in heavy-ion collisions are considered. The effect of transitions to the continuum on discrete transition probabilities is given via a simple prescription sa ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · December 1, 1979
Discusses the optimal choice of the basis for calculations of inner-shell excitations in the collision of heavy ions. Starting from a variational principle which minimises the time-integrated coupling strength, a relation between a model two-centre distanc ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · June 1, 1979
We calculate the δ-electron distribution resulting from heavy ion collisions with projectile energies above the Coulomb barrier. It is shown that the life time (Δτ≳10-21s) of superheavy composite systems causes pronounced oscillations in the ele ...
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Journal articlePhysics Letters B · March 26, 1979
In the present paper we investigate the compatibility of shock waves and phase transitions in nuclear matter. We show, that a continuous phase transition, i.e. the coexistence of the two phases, is not compatible with the existence of a sharp shock front. ...
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Journal articlePhysical Review Letters · January 1, 1979
This Letter discusses inner-shell excitation in collisions of very heavy ions (Z1+Z2140) in the framework of the quasimolecular model. The importance of multistep excitations and of coupling between continuum states is demonstrated. The 1sσ vacancy probabi ...
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Journal articlePhysical Review A · 1979
Complex population amplitudes for the excitation of magnetic sublevels of He(2p2)D1 and He(2s2p)P1 states in 2-keV He+ -He collisions have been determined by measuring the energy spectra of the corresponding autoionization electrons ejected at different an ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1978
Fast heavy ions penetrating through solids initiate density oscillations of the electron plasma, forming Mach cones if the projectile velocity exceeds a critical value cs. These Mach waves should lead to the directed emission of electrons from t ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · December 1, 1978
The influence of perturbative interactions is discussed in the frame-work of time-dependent perturbation theory. A characteristic time (to be called relaxation time), during which a given initial state of the system will be depleted, is defined. In case th ...
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Journal articleJournal of Physics A Mathematical and General · December 1, 1978
The authors discuss the solutions of the generalised gravitational field equations derived from the nonlinear Lagrangian for a limiting curvature theory and compare the free space solutions as well as the solutions for an extended star with the correspondi ...
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Journal articlePhysics Letters A · November 13, 1978
We propose that the spin polarization of delta electrons should be used as a measure of the strong magnetic fields (B∼1017 G) induced by the nuclear motion in collisions of very heavy ions. The polarization is typically of the order of 10-20 per ...
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Journal articlePhysics Letters B · September 25, 1978
We present quantitative calculations of positron emission dynamically induced in the collision of PbPb and PbU. The results are compared with recent measurements, yielding evidence for new processes characteristic for quantum electrodynamics of strong fiel ...
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Journal articleZeitschrift Fur Physik A · March 1, 1978
We show that in deep inelastic heavy ion collisions with Z1+Z2> 173 the spontaneous decay of the neutral vacuum by emission of positrons may be isolated from other competing positron producing processes. From the details of the sponta ...
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Journal articleZeitschrift Fur Physik A · March 1, 1978
The probability for 2p1/2σ-ionization in U-U and Pb-Pb collisions is calculated. The results are used to explain the measured impact parameter dependence for K-vacancy production in U-Pb collisions as the sum of direct ionization and strong rota ...
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Journal articlePhysics Letters A · February 6, 1978
Direct ionization of the 1sσ, 2sσ, 3sσ and 2p 1 2σ electronic states via radial coupling in the Pb-Pb quasimolecule is investigated as function of the impact parameter b. The ionization probability decreases exponentially like P(b)∼exp(- b a), w ...
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Journal articlePhysics Letters B · January 2, 1978
We present ab initio calculations of the quasimolecular K-X-ray spectrum from the Pb + Pb system, where both the Kd-hole amplitude and the radiation amplitude is calculated in first order perturbation theory. A comparison with the background radiation like ...
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Journal articleZeitschrift Fur Physik A · January 1, 1978
We derive an approximate analytical formula for the K-shell ionization in collisions of very heavy atoms. The impact parameter and bombarding energy dependence are well described. The binding energy of the bound state at closest approach enters in a simple ...
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Journal articlePhysical Review Letters · 1978
The azimuthal angular dependence and corresponding energy spectra have been measured for electrons ejected at 135° from the beam direction by autoionizing He atoms in the (2p2)D1 and (2s2p)P1 states, which were excited by 2000-eV He+ ions scattered through ...
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Journal articleJournal of Physics A General Physics · December 1, 1977
Dirac's equation has been considered in a Schwarzschild (Reissner-Nordstrom) background. Resonances in a continuum of states are found, similar to the Klein-Gordon case. Also the solutions of the Dirac and Klein-Gordon equations are investigated for an ext ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1977
Various possibilities for interpreting the recently observed X-rays from supposedly superheavy elements are studied. These X-rays can also be explained by atomic lines of superheavy elements from the Z=164 and Z=114 islands. ...
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Journal articleJournal of Physics G Nuclear Physics · December 1, 1977
Parastatistics with continuous order are proposed. The various parastatistics are used in scattering theory as an effective description accounting for the internal structure of composite particles (nuclei). Also investigated is the possibility that muons a ...
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Journal articlePhysics Letters A · November 14, 1977
We show that average excitation of the vacuum state in the presence of an external electric field can be described by an effective temperature kT = eE (2πm). We present a qualitative generalization of our result to other interactions. Some phenomenological ...
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Journal articleZeitschrift Fur Physik A Atoms and Nuclei · September 1, 1977
Transition rates for electrons in the superheavy elements Z=114, 126, 134, 145, 164 and 173 are calculated. K, L and M-shells are considered as final states. The 2 s-1 s transition of multipolarity M 1 is dominant for Z = 173 with a transition time of 10
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Journal articlePhysics Letters A · July 25, 1977
The electrostatic and gravitational fields of an extended spherically symmetric object is presented. The limit to a point-like object is discussed for Born-Infeld type of electrodynamics and it is shown, that the extreme Reissner-Nordstrøm field, where no ...
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Journal articlePhysical Review Letters · January 1, 1977
The theory of direct electron-positron pair production in the collision of heavy ions is formulated in the framework of the quasimolecular model. The pair production process acquires a collective nature for (Z1+Z2)>1 and can be understood as the shakeoff o ...
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Journal articlePhysics Letters B · November 22, 1976
There is a large discrepancy in published values of the critical distance in heavy-ion collisions. We have recalculated the critical distance by a more accurate method for symmetric collisions of point nuclei as a function of Z. The reasons for the discrep ...
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Journal articlePhysical Review D · January 1, 1976
The behavior of fermions interacting via vector gluons in the strong-coupling limit is investigated. A suitable coupling between the Dirac and the vector-gluon field gives rise to bound-state solutions. The coherent field approximation is employed to find ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · January 1, 1976
Amplitudes for radiative transitions in fast-rotating molecules and heavy-ion collisions are derived. The effect of the Coriolis force on the electron motion and on the radiative transition amplitude is formulated. The term in the transition amplitude depe ...
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Journal articlePhysical Review Letters · January 1, 1976
The direct (Coulomb) formation of electron vacancies in the 1sσ state of superheavy quasimolecules is investigated for the first time. Its dependence on the impact parameter, projectile energy, and its contribution from excitations into the continum and hi ...
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Journal articleJournal of Physics B Atomic and Molecular Physics · December 1, 1975
A general formulation of the collision between two heavy ions is presented. While this formalism may also be applied to nuclear structure problems, the emphasis is placed upon the electronic structure. Molecular and relativistic effects on the electronic m ...
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Journal articlePhysics Letters B · January 6, 1975
The inner shell molecular orbitals formed in heavy ion collisions become states of superheavy atoms as the two nuclei amalgamate. It is shown that there is a unique correspondence between the scattering energy, i.e., the distance of closest approach, and t ...
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Journal articlePhysical Review Letters · January 1, 1975
Intensity oscillations are observed in the quasimolecular K x-ray spectrum emitted in high-energy Ni58-Ni58 collisions. The oscillating structure is shown, theoretically, to reflect the existence of a two-step mechanism for the production of molecular-orbi ...
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Journal articlePhysical Review Letters · January 1, 1975
The expectation value of electrical charge in charged vacuum is calculated utilizing the Thomas-Fermi model. We find almost complete screening of the nuclear charge. For any given nuclear density there is an upper bound for the electrical potential. For no ...
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Journal articlePhysics Letters B · April 15, 1974
Three types of transitions exists in intermediate molecules occuring in heavy ion scattering: spontaneous radiative, induced non-radiative, and induced radiative decay. The latter ones yield an asymmetric angular distribution for molecular X-rays with resp ...
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Journal articleNuclear Physics Section B · January 21, 1974
The concept of over-critical fields, i.e. fields in which spontaneous, energy-less electron-position pair creation may occur, is discussed. It is shown that only a charged vacuum can be a stable ground state of the overcritical field. The time-dependent tr ...
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Journal articlePhysical Review Letters · January 1, 1974
The mechanisms of spontaneous and induced emission of radiation are derived from the Dirac equation in a rotating coordinate system. The molecular-orbital x-ray spectra exhibit a strong asymmetry with respect to the beam axis. The asymmetry peaks for the h ...
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Journal articlePhysical Review Letters · January 1, 1974
In critical or nearly critical heavy-ion collisions, induced as well as spontaneous energyless e-e+ pair creation result in the decay of the neutral vacuum. Induced transitions from the negative-energy continuum into a vacant molecular 1s level can occur e ...
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Journal articleAnnals of Physics · January 1, 1974
Recent disagreement between theoretical and experimental values of transition energies for outer states in muonic atoms is discussed in the range of 150-440 keV. A brief review of the present status of calculation of the theoretical contributions is given. ...
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Journal articleIl Nuovo Cimento A Series 11 · December 1, 1973
The mathematical properties of the solutions of the Dirac equation in over-critical external potentials are investigated. The 1/r Coulomb potential is treated as the limit R → 0 of cut-off Coulomb potentials (R is the cut-off parameter). The results are in ...
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Journal articleZeitschrift Fur Physik · June 1, 1972
Autoionization of positrons occurs as a fundamentally new process of quantum electrodynamics, if empty 1 s- or 2 p1/2- etc. electronic shells obtain binding energies larger than 2 mec2. This effect should be experimentally ...
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Journal articleZeitschrift Fur Physik · February 1, 1972
When the charge of a nucleus exceeds Z=Zcr≈ 164-172 the energy of the 1 s-electron level is lowered beyond the critical value of -mec2. Then this bound level is degenerated with negative energy continuum solutions of the Di ...
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Journal articlePhysical Review Letters · January 1, 1972
The 1s bound state of superheavy atoms and molecules reaches a binding energy of -2mc2 at 169. It is shown that the K shell is still localized in r space even beyond this critical proton number and that it has a width Γ (several keV large) which is a posit ...
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