Scholars@Duke
John H Kelley

John H Kelley

Adjunct Associate Professor of Physics in the Department of Physics
Physics
jhkelley@duke.edu
Box 90305, Durham, NC 27708-0305
Rm 418 TUNL, Triangle Universities Nuclear, Durham, NC 27708

Selected Publications

New energy for the 133-keV resonance in the Na 23 (p,γ) Mg 24 reaction and its impact on nucleosynthesis in globular clusters

Journal Article Physical Review C · September 1, 2021 Globular cluster stars exhibit star-to-star anticorrelations between oxygen and sodium in their atmospheres. An improved description of the sodium-destroying Na23+p reaction rates is essential to understanding these observations. We present an energy analy ... Full text Cite

Experimental study of Cl 35 excited states via S 32 (α,p)

Journal Article Physical Review C · May 30, 2019 Background: The presolar grains originating in oxygen-neon novae may be identified more easily than those of other stellar sources if their sulfur isotopic ratios (S33/S32 and S34/S32) are compared with the theoretical ones. The accuracy of such a comparis ... Full text Cite

Excited states of Ca 39 and their significance in nova nucleosynthesis

Journal Article Physical Review C · November 26, 2018 Background: Discrepancies exist between the observed abundances of argon and calcium in oxygen-neon nova ejecta and those predicted by nova models. An improved characterization of the K38(p,γ)Ca39 reaction rate over the nova temperature regime (∼0.1-0.4 GK ... Full text Cite

Astrophysical relevance of the low-energy dipole strength of 206Pb

Conference EPJ Web of Conferences · May 16, 2018 The dipole strength of 206Pb was studied below the neutron separation energy using photon scattering experiments at the HIGS facility. Utilizing the technique of nuclear resonance fluorescence with 100% linearly-polarized photon beams, the spins, parities, ... Full text Cite

Energy levels of light nuclei A = 12

Journal Article Nuclear Physics A · December 1, 2017 A review of evidence on the properties of the A=12 nuclei, with emphasis on material leading to information about the structure of the A=12 systems. ... Full text Cite

Pygmy and core polarization dipole modes in 206Pb: Connecting nuclear structure to stellar nucleosynthesis

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · October 10, 2017 A high-resolution study of the electromagnetic response of 206Pb below the neutron separation energy is performed using a γ→,γ′) experiment at the HIγ→S facility. Nuclear resonance fluorescence with 100% linearly polarized photon beams is used to measure s ... Full text Cite

Capture cross sections on unstable nuclei

Conference EPJ Web of Conferences · September 13, 2017 Accurate neutron-capture cross sections on unstable nuclei near the line of beta stability are crucial for understanding the s-process nucleosynthesis. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to th ... Full text Cite

Dipole response of the odd-proton nucleus 205Tl up to the neutron-separation energy

Journal Article Journal of Physics G: Nuclear and Particle Physics · October 17, 2016 The low-lying electromagnetic dipole strength of the odd-proton nuclide 205Tl has been investigated up to the neutron separation energy exploiting the method of nuclear resonance fluorescence. In total, 61 levels of 205Tl have been identified. The measured ... Full text Cite

The decay pattern of the Pygmy Dipole Resonance of 140Ce

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · May 10, 2016 The decay properties of the Pygmy Dipole Resonance (PDR) have been investigated in the semi-magic N=82 nucleus 140Ce using a novel combination of nuclear resonance fluorescence and γ-γ coincidence techniques. Branching ratios for transitions to low-lying e ... Full text Cite

Exploratory study of fission product yields of neutron-induced fission of U 235, U 238, and Pu 239 at 8.9 MeV EXPLORATORY STUDY of FISSION PRODUCT YIELDS ... C. BHATIA et al.

Journal Article Physical Review C - Nuclear Physics · June 5, 2015 Using dual-fission chambers each loaded with a thick (200-400-mg/cm2) actinide target of 235,238U or Pu239 and two thin (∼10-100-μg/cm2) reference foils of the same actinide, the cumulative yields of fission products ranging from Sr92 to Nd147 have been me ... Full text Cite

Nuclear structure studies with gamma-ray beams

Conference EPJ Web of Conferences · May 28, 2015 In stable and weakly bound neutron-rich nuclei, a resonance-like concentration of dipole states has been observed for excitation energies below the neutron-separation energy. This clustering of strong dipole states has been named the Pygmy Dipole Resonance ... Full text Cite

Decay pattern of the pygmy dipole resonance in 140Ce

Conference EPJ Web of Conferences · May 28, 2015 The decay behavior of low-lying dipole states in 140Ce was investigated exploiting the γ3-setup at the HIγS facility using quasi-monochromatic photon beams. Branching ratios of individual excited states as well as average branching ratios to low-lying stat ... Full text Cite

Dipole strength distributions from HIGS Experiments

Conference EPJ Web of Conferences · May 28, 2015 A series of photon scattering experiments has been performed on the double-beta decay partners 76Ge and 76Se, in order to investigate their dipole response up to the neutron separation threshold. Gamma-ray beams from bremsstrahlung at the S-DALINAC and fro ... Full text Cite

QPM analysis of 205TI nuclear excitations below the giant dipole resonance

Conference EPJ Web of Conferences · May 28, 2015 We analysed our experimental recent findings of the dipole response of the odd-mass stable nucleus 205Tl within the quasi-particle phonon model. Using the phonon basis constructed for the neighbouring 204Hg and wave function configurations for 205Tl consis ... Full text Cite

Separation of the 1+/1- parity doublet in 20Ne

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · February 4, 2015 The (J, T)=(1, 1) parity doublet in 20Ne at 11.26 MeV is a good candidate to study parity violation in nuclei. However, its energy splitting is known with insufficient accuracy for quantitative estimates of parity violating effects. To improve on this unsa ... Full text Cite

Magnetic dipole strength in Xe 128 and Xe 134 in the spin-flip resonance region

Journal Article Physical Review C - Nuclear Physics · November 10, 2014 The magnetic dipole strength in the energy region of the spin-flip resonance is investigated in Xe128 and Xe134 using quasimonoenergetic and linearly polarized γ-ray beams at the High-Intensity γ-Ray Source facility in Durham, North Carolina, USA. Absorpti ... Full text Cite

Dual-fission chamber and neutron beam characterization for fission product yield measurements using monoenergetic neutrons

Journal Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · September 1, 2014 A program has been initiated to measure the energy dependence of selected high-yield fission products used in the analysis of nuclear test data. We present out initial work of neutron activation using a dual-fission chamber with quasi-monoenergetic neutron ... Full text Cite

Isospin properties of electric dipole excitations in 48Ca

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · March 7, 2014 Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly ... Full text Cite

Photoexcitation of the stable tl isotopes below the neutron separation energy

Conference Acta Physica Polonica B · February 1, 2014 Although the systematics of the Pygmy Dipole Resonance was established in several stable even-even nuclei, the collectivity of this mode, explained in a macroscopic picture as an oscillation of a neutron skin against an isospin symmetric proton-neutron cor ... Full text Cite

Constraining nuclear photon strength functions by the decay properties of photo-excited states

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · December 18, 2013 A new approach for constraining the low-energy part of the electric dipole Photon Strength Function (E1-PSF) is presented. Experiments at the Darmstadt High-Intensity Photon Setup and the High Intensity γ→-Ray Source have been performed to investigate the ... Full text Cite

Dipole response of 76Se above 4 MeV

Journal Article Physical Review C - Nuclear Physics · December 6, 2013 The dipole response of 3476Se in the energy range from 4 to 9 MeV has been analyzed using a (γâ-, γ′) polarized photon scattering technique, performed at the High Intensity γ-Ray Source facility at Triangle Universities Nuclear Laboratory, to complement pr ... Full text Cite

Nuclear deformation and neutron excess as competing effects for pygmy dipole strength

Journal Article · November 8, 2013 The electromagnetic dipole strength below the neutron-separation energy has been studied for the xenon isotopes with mass numbers A = 124, 128, 132, and 134 in nuclear resonance fluorescence experiments using the ELBE bremsstrahlung facility at Helmholtz-Z ... Link to item Cite

Low-lying dipole strength of the open-shell nucleus 94Mo

Journal Article Physical Review C - Nuclear Physics · October 29, 2013 The low-lying dipole strength of the open-shell nucleus 94Mo was studied via the nuclear resonance fluorescence technique up to 8.7 MeV excitation energy at the bremsstrahlung facility at the Superconducting Darmstadt Electron Linear Accelerator (S-DALINAC ... Full text Cite

Photoresponse of 60Ni below 10-MeV excitation energy: Evolution of dipole resonances in fp-shell nuclei near N=Z

Journal Article Physical Review C - Nuclear Physics · October 7, 2013 Background: Within the last decade, below the giant dipole resonance the existence of a concentration of additional electric dipole strength has been established. This accumulation of low-lying E1 strength is commonly referred to as pygmy dipole resonance ... Full text Cite

Cross-section measurements of the 86Kr(γ,n) reaction to probe the s-process branching at 85Kr.

Journal Article Physical review letters · September 2013 We have carried out photodisintegration cross-section measurements on 86Kr using monoenergetic photon beams ranging from the neutron separation energy, S(n) = 9.86  MeV, to 13 MeV. We combine our experimental 86Kr(γ,n)85Kr cross section with results from o ... Full text Cite

The high-efficiency γ-ray spectroscopy setup γ 3 at HIγS

Journal Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · June 17, 2013 The existing Nuclear Resonance Fluorescence (NRF) setup at the HIγS facility at the Triangle Universities Nuclear Laboratory at Duke University has been extended in order to perform γ-γ coincidence experiments. The new setup combines large volume LaBr3:Ce ... Full text Cite

Decay pattern of the pygmy dipole resonance in 60Ni

Journal Article Physical Review C - Nuclear Physics · May 15, 2013 Spin-1 states in 60Ni were excited with the (γâ -, γ′) reaction, exploiting the High Intensity γâ - -ray Source at Triangle University Nuclear Laboratory. This facility is capable of providing fully linearly polarized, quasimonochromatic, Compton-backscatt ... Full text Cite

Pygmy dipole strength in 86Kr and systematics of N=50 isotones

Journal Article Physical Review C - Nuclear Physics · February 8, 2013 The dipole strength of the N=50 nucleus 86Kr was studied in photon-scattering experiments using bremsstrahlung produced with electron beams of energies of 7.9 and 11.2 MeV delivered by the linear accelerator ELBE as well as using quasimonoenergetic and lin ... Full text Cite

Fine structure of the giant M1 resonance in 90Zr.

Journal Article Physical review letters · January 2013 The M1 excitations in the nuclide 90Zr have been studied in a photon-scattering experiment with monoenergetic and linearly polarized beams from 7 to 11 MeV. More than 40 J(π)=1+ states have been identified from observed ground-state transitions, revealing ... Full text Cite

Constraining nuclear photon strength functions by the decay properties of photo-excited states

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · 2013 Cite

Evidence for radiative coupling of the pygmy dipole resonance to excited states

Journal Article Physical Review C - Nuclear Physics · November 26, 2012 The photoabsorption cross section and ground-state branching ratio of 142Nd were measured using quasimonoenergetic γ-ray beams at several beam energies. Two peaks corresponding to the pygmy dipole resonance (PDR) were identified. The branching ratios were ... Full text Cite

Searching for illicit materials using nuclear resonance fluorescence stimulated by narrow-band photon sources

Journal Article Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms · August 15, 2012 We report the results of an experimental study of the sensitivity of two distinct classes of systems that exploit nuclear resonance fluorescence (NRF) to search for illicit materials in containers. One class of systems is based on the direct detection of N ... Full text Cite

Electromagnetic dipole strength of 136Ba below the neutron separation energy

Journal Article Physical Review C - Nuclear Physics · July 17, 2012 The electromagnetic dipole strength of the nucleus 136Ba has been investigated. Two measurements were performed with electron energies of 7.0 and 11.4 MeV at the bremsstrahlung facility at the ELBE accelerator of the Helmholtz-Zentrum Dresden-Rossendorf. P ... Full text Cite

Photodisintegration cross section of the reaction 4He(γ,n)3He at the giant dipole resonance peak

Journal Article Physical Review C - Nuclear Physics · June 1, 2012 The photodisintegration cross section of 4He into a neutron and helion was measured at incident photon energies of 27.0, 27.5, and 28.0 MeV. A high-pressure 4He-Xe gas scintillator served as target and detector while a pure Xe gas scintillator was used for ... Full text Cite

Energy levels of light nuclei A=11

Journal Article Nuclear Physics A · April 15, 2012 A review of evidence on the properties of the A=11 nuclei, with emphasis on material leading to information about the structure of the A=11 systems. © 2012 Elsevier B.V. ... Full text Cite

Dipole response of 238U to polarized photons below the neutron separation energy

Journal Article Physical Review C - Nuclear Physics · April 2, 2012 Nuclear resonance fluorescence experiments were carried out at the High-Intensity γ-ray Source facility at Triangle Universities Nuclear Laboratory to characterize the low-energy dipole structure of 238U using 100% linearly polarized photon beams from 2.0 ... Full text Cite

Photodisintegration cross section of the reaction (4)He(γ,p)(3)H between 22 and 30 MeV.

Journal Article Physical review letters · January 2012 The two-body photodisintegration cross section of (4)He into a proton and triton was measured with monoenergetic photon beams in 0.5 MeV energy steps between 22 and 30 MeV. High-pressure (4)He-Xe gas scintillators of various (4)He/Xe ratios served as targe ... Full text Cite

Energy separation of the 1+/1- parity doublet in 20Ne

Conference Journal of Physics: Conference Series · January 1, 2012 The parity doublet of 1+/1- states of Ne-20 at 11.26 MeV excitation energy is one of the best known test cases to study the weak part of the nuclear Hamiltonian. The feasibility of parity violation experiments depend on the effective nuclear enhancement fa ... Full text Cite

Cross-section measurements of the 86Kr(γ, n) reaction to probe the s-process branching at 85Kr

Conference Journal of Physics: Conference Series · January 1, 2012 For the first time, cross-section measurements were carried out for the 86Kr(γ, n) reaction in order to probe the s-process branching point nucleus 85Kr. The branching point nuclei in the s-process path are of importance in testing and constraining the nuc ... Full text Cite

Two-body photodisintegration of 3He between 7 and 16 MeV

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · August 11, 2011 A comprehensive data set is reported for the two-body photodisintegration cross section of 3He using mono-energetic photon beams at eleven energies between 7.0 and 16.0 MeV. A He3+Xe high-pressure gas scintillator served as target and detector. Although ou ... Full text Cite

Cross-section measurements of neutron-induced reactions on GaAs using monoenergetic beams from 7.5 to 15 MeV

Journal Article Physical Review C - Nuclear Physics · April 28, 2011 Cross-section measurements for neutron-induced reactions on GaAs have been carried out at twelve different neutron energies from 7.5 to 15 MeV using the activation technique. The monoenergetic neutron beams were produced via the H2(d,n)He3 reaction. GaAs s ... Full text Cite

Discrete deexcitations in U235 below 3 MeV from nuclear resonance fluorescence

Journal Article Physical Review C - Nuclear Physics · April 21, 2011 Gamma-ray transitions in U235 were measured using the (γ, γ') reaction below 3 MeV. The nuclear-resonance-fluorescence experiment was carried out at the High-Intensity γ-ray Source facility using nearly monoenergetic and circularly polarized photon beams. ... Full text Cite

Discovery of low-lying E1 and M1 strengths in Th232

Journal Article Physical Review C - Nuclear Physics · March 25, 2011 Properties of low-energy dipole states in Th232 have been investigated with the nuclear resonance fluorescence technique. The present work used monoenergetic γ-ray beams at energies of 2-4 MeV from the high-intensity γ-ray source at Triangle Universities N ... Full text Cite

Investigation of low-lying electric dipole strength in the semimagic nucleus Ca44

Journal Article Physical Review C - Nuclear Physics · March 7, 2011 The dipole-strength distribution in the semimagic nucleus Ca44 has been measured up to 10 MeV excitation energy in photon-scattering experiments using bremsstrahlung and monoenergetic 100% linearly polarized photon beams. The combination of both measuremen ... Full text Cite

Cross section measurements of neutron induced reactions on GaAs using monoenergetic beams from 7.5 to 15 MeV

Journal Article Journal of Physics: Conference Series · January 1, 2011 Cross section measurements for the neutron induced reactions on GaAs have been carried out at ten different neutron energies from 7.5 to 15 MeV, using the activation technique. The monoenergetic neutron beams were produced via the 2H(d,n)3He reaction, know ... Full text Cite

Coarse and fine structure of the pygmy dipole resonance

Conference Journal of Physics: Conference Series · January 1, 2011 High resolution and sensitivity studies of the nuclear dipole response in 138Ba have been performed in (γ, γ′) experiment. The electric dipole character of the "pygmy" mode was experimentally verified for excitations from 4.0 to 8.5 MeV. Experimental findi ... Full text Cite

Fine structure of the giant M1 resonance in 90Zr

Conference Journal of Physics: Conference Series · January 1, 2011 M1 excitations in the 90Zr nucleus have been studied in a photon-scattering experiment with monoenergetic and 100% linearly-polarized beams from 7 to 11 MeV. More than 40 Jπ = 1+ states were identified for the first time from the observed ground-state tran ... Full text Cite

Energy levels of light nuclei A=3

Journal Article Nuclear Physics A · December 15, 2010 A compilation of experimental and theoretical information is presented on the mass 3 systems 3n, 3H, 3He and 3p. Emphasis is on advances since the previous evaluation Tilley et al. (1987) [1987TI07] such as, (1) detailed calculations of the vector and tens ... Full text Cite

Measurement of the Am241(γ,n)Am240 reaction in the giant dipole resonance region

Journal Article Physical Review C - Nuclear Physics · November 30, 2010 The photodisintegration cross section of the radioactive nucleus Am 241 has been obtained using activation techniques and monoenergetic γ-ray beams from the HIγS facility. The induced activity of Am 240 produced via the Am241(γ,n) reaction was measured in ... Full text Cite

Ratio of germanium detector peak efficiencies at photon energies of 4.4 and 11.7 MeV: Experiment versus simulation

Journal Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · June 1, 2010 Full-energy peak efficiencies of germanium detectors are frequently investigated at γ-ray energies below 4 MeV using calibrated radioactive sources, while very accurate peak efficiencies for higher photon energies are essentially non-existent. Peak efficie ... Full text Cite

Neutron-deuteron analyzing power data at 19.0 MeV

Journal Article Physical Review C - Nuclear Physics · February 23, 2010 Measurements of neutron-deuteron (n-d) analyzing power Ay(θ) at En=19.0 MeV are reported at 16 angles from θc.m.=46.7 to 152.0°. The objective of the experiment is to better characterize the discrepancies between n-d data and the predictions of three-nucle ... Full text Open Access Cite

Spectral structure of the pygmy dipole resonance.

Journal Article Physical review letters · February 2010 High-sensitivity studies of E1 and M1 transitions observed in the reaction 138Ba(gamma,gamma{'}) at energies below the one-neutron separation energy have been performed using the nearly monoenergetic and 100% linearly polarized photon beams of the HIgammaS ... Full text Open Access Cite

Transmission-based detection of nuclides with nuclear resonance fluorescence using a quasimonoenergetic photon source

Journal Article Journal of Applied Physics · November 10, 2009 We provide a detailed experimental validation of the concept of transmission-based isotope detection. The dominant background processes in this class of systems were measured by studying the detection of U238 with a quasimonochromatic (ΔE/E∼3%) photon beam ... Full text Cite

Cross sections for U238(n,n'γ) and U238(n,2nγ) reactions at incident neutron energies between 5 and 14 MeV

Journal Article Physical Review C - Nuclear Physics · August 6, 2009 Precision measurements of U238(n,n'γ) and U238(n,2nγ) partial cross sections have been performed at Triangle Universities Nuclear Laboratory (TUNL) to improve crucial data needed for testing nuclear reaction models in the actinide mass region. A pulsed and ... Full text Cite

Photodisintegration cross section of241Am

Journal Article AIP Conference Proceedings · May 5, 2009 The photodisintegration cross section of radioactive 241Am has been obtained for the first time using monoenergetic γ-ray beams from the HIγS facility. The induced activity of240Am produced via the 241Am(γ,n) reaction in the γ-ray energy range from 9.5 to ... Full text Cite

Dipole-strength distributions below the giant dipole resonance in the stable even-mass molybdenum isotopes

Conference AIP Conference Proceedings · May 5, 2009 Dipole-strength distributions in the stable even-mass molybdenum isotopes up to the neutron-separation energies have been studied in photon-scattering experiments with bremsstrahlung at the superconducting electron accelerator ELBE at the Research Center D ... Full text Cite

Recent results from the excitation of dipole states at the HlγS facility

Conference AIP Conference Proceedings · April 23, 2009 High-sensitivity studies of El and Ml excitations observed in the 138Ba(γ,γ') reaction at energies below the neutron emission threshold have been performed. The electric dipole character of the so-called "pygmy" mode was experimentally verified for excitat ... Full text Cite

Measurement of the Am241(n,2n) reaction cross section from 7.6 MeV to 14.5 MeV

Journal Article Physical Review C - Nuclear Physics · May 27, 2008 The (n,2n) cross section of the radioactive isotope Am241 (T1/2=432.6 y) has been measured in the incident neutron energy range from 7.6 to 14.5 MeV in steps of a few MeV using the activation technique. Monoenergetic neutron beams were produced via the H2( ... Full text Cite

Pulsed and monoenergetic beams for neutron cross-section measurements using activation and scattering techniques at Triangle Universities Nuclear Laboratory

Journal Article Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms · August 1, 2007 In support of the Stewardship Science Academic Alliances initiative, an experimental program has been developed at Triangle Universities Nuclear Laboratory (TUNL) to measure (n,xn) cross-sections with both in-beam and activation techniques with the goal of ... Full text Cite

Study of collective dipole excitations below the giant dipole resonance at HIγS

Journal Article AIP Conference Proceedings · April 4, 2007 The High-Intensity Gamma-ray Source utilizing intra-cavity back-scattering of free electron laser photons from relativistic electrons allows one to produce a unique beam of high-flux gamma rays with 100% polarization and selectable energy and energy resolu ... Full text Cite

Missing dipole excitation strength below the particle threshold

Conference Proceedings of Science · January 1, 2007 High sensitivity studies of E1 andM1 excitations fromthe 138Ba(γ,γ') reaction at energies close to the neutron emission threshold have been performed. The electric dipole character of the "pygmy" mode was experimentally verified for excitations from 5.5-8. ... Cite

Measurement of the relative longitudinal spin-dependent total cross-section difference in n→-d→ scattering

Journal Article Physical Review C - Nuclear Physics · March 23, 2006 We report relative measurements of the n→-d→ longitudinal spin-dependent total cross-section difference (ΔσL)d, at En(lab) = 5.0, 6.88, and 9.0 MeV. The deuteron target was polarized via dynamic nuclear polarization at 250 mK in a 2.5-T external magnetic f ... Full text Cite

Low-energy dipole modes of excitation below the neutron separation energy

Journal Article AIP Conference Proceedings · March 13, 2006 The nuclear resonance fluorescence experiments have been performed at the High Intensity Gamma Source (HIγS) on 138Ba nuclei using four 60% efficient HPGe detectors. Excitation energies, spin, parities, and decay branching ratios were measured for the low- ... Full text Cite

Photo-induced population of the h11/2 isomeric states in (γ, n) reactions

Conference AIP Conference Proceedings · March 13, 2006 The mechanism of excitation of isomeric h11/2 states in nuclei around the closed shell at N=82 have been studied at the High-Intensity Gamma Source (HIγS). We have taken advantage of the monoenergetic (ΔE/E=1.5%) and pulsed γ-ray-beam from HIγS to perform ... Full text Cite

Exclusive Photoproduction of the Cascade Hyperons

Journal Article The Physica Review C · December 2005 Link to item Cite

TUNL nuclear data evaluation program

Conference AIP Conference Proceedings · May 24, 2005 The Nuclear Data Evaluation program at Triangle Universities Nuclear Lab (TUNL) performs nuclear structure evaluation of nuclei in the A=2-20 mass range. This group continues to produce evaluations in the Energy Levels of Light Nuclei series using the form ... Full text Cite

Photon analyzing power for the three-body breakup of 3He at Eγ = 15.0 MeV

Journal Article AIP Conference Proceedings · May 6, 2005 Photon analyzing power for the three-body breakup of 3He has been studied at Eγ = 15.0 MeV. The measurements were done at the HIγS facility at Duke University. © 2005 American Institute of Physics. ... Full text Cite

Exclusive ρ0 meson electroproduction from hydrogen at CLAS

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · January 13, 2005 The longitudinal and transverse components of the cross section for the ep → e′ pρ0 reaction were measured in Hall B at Jefferson Laboratory using the CLAS detector. The data were taken with a 4.247 GeV electron beam and were analyzed in a range of xB from ... Full text Cite

The high intensity gamma-ray source HIGS and recent measurements

Journal Article Nucl. Instr. Methods B. · 2005 The high intensity γ-ray source (HIγS) utilizes intra-cavity backscattering of free electron laser photons from the Duke electron storage ring to produce a unique monoenergetic beam of high-flux γ-rays with high polarization and selectable e ... Cite

Energy level of light nuclei A=8,9,10

Journal Article Nuclear Physics · December 2004 Link to item Cite

Proton source size measurements in the eA-->e'ppX reaction.

Journal Article Physical review letters · November 2004 Two-proton correlations at small relative momentum q were studied in the eA(3He,4He,C,Fe)-->e(')ppX reaction at E(0)=4.46 GeV using the CLAS detector at Jefferson Lab. The enhancement of the correlation function at small q was found to be in accordance wit ... Full text Cite

Proton removal from 8B, 9C, and 12C on Si at 20-70 MeV/nucleon

Journal Article Physical Review C - Nuclear Physics · January 1, 2004 A Si detector telescope, in which alternating thick and thin Si elements served as both targets and detectors, was used to measure the energy dependence of the inclusive one-proton-removal cross sections σ1p of 8B, 9C, and 12C on a Si target. A similar det ... Full text Cite

Two-Nucleon Momentum Distributions Measured in 3He(e,e'pp)n

Journal Article Physical Review Letters · 2004 Link to item Cite

Measurement of beam-spin asymmetries for [Formula Presented] electroproduction above the baryon resonance region

Journal Article Physical Review D - Particles, Fields, Gravitation and Cosmology · January 1, 2004 We report the first evidence for a nonzero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic kinematic region. Data for the reaction [Formula Presented] have been obtained using a polarized electron beam of 4.3 ... Full text Cite

Measurement of the polarized structure function σ LT′ for p(e→,e′π+)n in the Δ(1232) resonance region

Journal Article Physical Review C - Nuclear Physics · January 1, 2004 The polarized longitudinal-transverse structure function σ LT′, has been measured using the p(e→, e′ π+)n reaction in the Δ(1232) resonance region at Q2=0.40 and 0.65 GeV2. No previous σ LT′ data exist for this reaction channel. The kinematically complete ... Full text Cite

Measurement of the proton spin structure function g1(x,Q2) for Q2 from 0.15 to 1.6 GeV2 with CLAS.

Journal Article Physical review letters · November 2003 Double-polarization asymmetries for inclusive ep scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a longitudinally polarized NH3 target in the CLAS detector. The polarized structure function g(1 ... Full text Cite

First measurement of transferred polarization in the exclusive ep-->e'K+Lambda--> reaction.

Journal Article Physical review letters · April 2003 The first measurements of the transferred polarization for the exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using the CLAS spectrometer. A 2.567 GeV beam was used to measure the hyperon polarization over Q2 from 0. ... Full text Cite

The [Formula Presented] reaction at astrophysically relevant energies

Journal Article Physical Review C - Nuclear Physics · January 1, 2003 The [Formula Presented] reaction was studied by detecting the [Formula Presented]-rays produced when 100-, 130-, and [Formula Presented] polarized protons were stopped in a thick [Formula Presented] target. Polarized and unpolarized incident beams were use ... Full text Cite

Measurement of the polarized structure function [Formula Presented] for [Formula Presented] in the [Formula Presented] resonance region

Journal Article Physical Review C - Nuclear Physics · January 1, 2003 The polarized longitudinal-transverse structure function [Formula Presented] has been measured in the [Formula Presented] resonance region at [Formula Presented] and [Formula Presented] Data for the [Formula Presented] reaction were taken at Jefferson Lab ... Full text Cite

Kinematically complete measurement of the proton structure function [Formula Presented] in the resonance region and evaluation of its moments

Journal Article Physical Review D - Particles, Fields, Gravitation and Cosmology · January 1, 2003 We measured the inclusive electron-proton cross section in the nucleon resonance region [Formula Presented] at momentum transfers [Formula Presented] below [Formula Presented] with the CLAS detector. The large acceptance of CLAS allowed the measurement of ... Full text Cite

The 10B(p→, γ)11C reaction at astrophysically relevant energies

Journal Article Physical Review C - Nuclear Physics · January 1, 2003 The 10B(p→, γ)11C reaction was studied by detecting the γ-rays produced when 100-, 130-, and 160-keV polarized protons were stopped in a thick 10B target. Polarized and unpolarized incident beams were used to measure the cross section and vector analyzing ... Full text Cite

η photoproduction on the proton for photon energies from 0.75 to 1.95 GeV

Journal Article Physical Review Letters · November 25, 2002 η photoproduction on the proton for photon energies from 0.75 to 1.95 GeV was discussed. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the production process. Comparison with preliminary result ... Cite

Eta photoproduction on the proton for photon energies from 0.75 to 1.95 GeV.

Journal Article Physical review letters · November 2002 Differential cross sections for gammap-->etap have been measured with tagged real photons for incident photon energies from 0.75 to 1.95 GeV. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the p ... Full text Cite

Coupling effects in the elastic scattering of 6He on 12C

Journal Article Physical Review C - Nuclear Physics · September 1, 2002 To study the effect of the weak binding energy on the interaction potential between a light exotic nucleus and a target, elastic scattering of 6He at 38.3 MeV/nucleon on a 12C target was measured at Grand Accélérateur National d'Ions Lourds (GANIL). The 6H ... Full text Cite

Q2 Dependence of quadrupole strength in the gamma*p --> Delta(+)(1232) --> p pi(0) transition.

Journal Article Physical review letters · March 2002 Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q2 dependence of the ma ... Full text Cite

First measurement of the double spin asymmetry in e→ p→ → e′ π+ n in the resonance region

Journal Article Physical Review Letters · February 25, 2002 The double spin asymmetry for the →e→p → e;π+ n channel was measured for the first time. A comparison with phenomenological models showed the high sensitivity of this observable to resonance contributions. The sign and magnitude of the measured assymmetry ... Cite

First measurement of the double spin asymmetry in (-->)e(-->)p-->e(prime)pi(+)n in the resonance region.

Journal Article Physical review letters · February 2002 The double spin asymmetry in the (-->)e(-->)p --> e(prime)pi(+)n reaction has been measured for the first time in the resonance region for four-momentum transfer Q2 = 0.35-1.5 GeV(2). Data were taken at Jefferson Lab with the CLAS detector using a 2.6 GeV ... Full text Cite

Identification of the Jπ=1- two-phonon state of 88Sr

Journal Article Physical Review C - Nuclear Physics · January 1, 2002 The linearly polarized γ-ray beam produced by the HIγS facility has been used to determine the parity of two previously known dipole excitations in 88Sr. The azimuthal asymmetry of γ rays produced in the process of nuclear resonance fluorescence indicated ... Full text Cite

[Formula Presented] reaction below [Formula Presented]

Journal Article Physical Review C - Nuclear Physics · January 1, 2002 The [Formula Presented] reaction was studied at incident energies of [Formula Presented] and 80 keV at the Triangle Universities Nuclear Laboratory (TUNL) using beams from a polarized ion source. The present study was the logical progression of a previous ... Full text Cite

Energy levels of light nuclei A=5,6,7

Journal Article Nuclear Physics · January 2002 A review of the evidence on the properties of the nuclei A=5,6 and 7, with emphasis on material leading to information about the structure of the A=5,6,7 systems. ... Link to item Cite

Identification of the [Formula Presented] two-phonon state of [Formula Presented]

Journal Article Physical Review C - Nuclear Physics · January 1, 2002 The linearly polarized γ-ray beam produced by the [Formula Presented] facility has been used to determine the parity of two previously known dipole excitations in [Formula Presented] The azimuthal asymmetry of γ rays produced in the process of nuclear reso ... Full text Cite

3H(p→, γ)4He reaction below Ep = 80 keV

Journal Article Physical Review C - Nuclear Physics · January 1, 2002 The 3H(p→, γ)4He reaction was studied at incident energies of Ep = 40 and 80 keV at the Triangle Universities Nuclear Laboratory (TUNL) using beams from a polarized ion source. The present study was the logical progression of a previous study of the 2H(p→, ... Full text Cite

Photoproduction of the rho(0) meson on the proton at large momentum transfer.

Journal Article Physical review letters · October 2001 The differential cross section, d sigma/dt, for rho(0) meson photoproduction on the proton above the resonance region was measured up to a momentum transfer -t = 5 GeV2 using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The rho( ... Full text Cite

Coupling effects in the elastic scattering of the exotic nucleus 6He on protons

Journal Article Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics · September 27, 2001 Cross sections for the elastic scattering of 6He radioactive nuclear beam on proton targets have been measured at 38.3 MeV/nucleon. With a view to test the ability of general optical potentials to reproduce the data for scattering of unstable nuclei, the p ... Full text Cite

Ratio of S factors for [Formula Presented] reactions on [Formula Presented] and [Formula Presented] at astrophysically relevant energies

Journal Article Physical Review C - Nuclear Physics · January 1, 2001 We present measurements of the [Formula Presented] S factor ratio at [Formula Presented] The overall result of [Formula Presented] is in good agreement with the value of this ratio obtained from previous experimental values of the S factors for the [Formul ... Full text Cite

Production of A = 6,7 nuclides in the α+α reaction and cosmic ray nucleosynthesis

Journal Article Physical Review C - Nuclear Physics · January 1, 2001 Cross sections for production of 6He, 6Li, 7Li, and 7Be in the α+α reaction were measured at bombarding energies of 159.3, 279.6, and 619.8 MeV and are found to decrease rapidly with increasing energy. These cross sections are essential for the calculation ... Full text Cite

Exclusive electroproduction of [Formula Presented] mesons at 4.2 GeV

Journal Article Physical Review C - Nuclear Physics · January 1, 2001 We studied the exclusive reaction [Formula Presented] using the [Formula Presented] decay mode. The data were collected using a 4.2 GeV incident electron beam and the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator F ... Full text Cite

Observation of exclusive deeply virtual compton scattering in polarized electron beam asymmetry measurements

Journal Article Physical Review Letters · January 1, 2001 We report the first results of the beam-spin asymmetry measured in the reaction e→p → epγ at a beam energy of 4.25 GeV. A large asymmetry with a sinφ modulation is observed, as predicted for the interference term of deeply virtual compton scattering (DVCS) ... Full text Cite

Electroproduction of the Λ(1520) hyperon

Journal Article Physical Review C - Nuclear Physics · January 1, 2001 The reaction [Formula Presented] with [Formula Presented] was studied at electron beam energies of 4.05, 4.25, and 4.46 GeV, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The [Formula Presented] [Formula Presented] and W de ... Full text Cite

Slope of the astrophysical S factor for the [Formula Presented] reaction

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 Polarized proton beams of 80 and 60 keV, and a biased target have been used to determine the slope of the astrophysical S factor for the [Formula Presented] reaction from direct measurements at proton energies from 40 to 100 keV for capture to both the gro ... Full text Cite

New photodisintegration threshold observable in [Formula Presented]

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 Measurements of the cross section, vector and tensor analyzing powers, and linear gamma-ray polarization in the radiative capture reactions [Formula Presented] and [Formula Presented] at c.m. energies in the range 0–53 keV allow the determination of the re ... Full text Cite

The [Formula Presented] reaction below 100 keV

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 The [Formula Presented] reaction was studied by measuring the [Formula Presented] rays that were produced when 80–100-keV polarized protons were stopped in a thick [Formula Presented] target. Cross sections and vector analyzing powers at [Formula Presented ... Full text Cite

First measurement of the near-threshold 2H(γ→,n)p analyzing power using a free-electron laser based γ-ray source

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 The first measurement of the 2H(γ→,n)p analyzing power near threshold has been performed using the High-Intensity Gamma-ray Source (HIGS) at the Duke Free-Electron Laser Laboratory. A 3.58 MeV γ-ray beam having an energy resolution of 2.5% and 100% linear ... Full text Cite

First measurement of the near-threshold [Formula Presented] analyzing power using a free-electron laser based [Formula Presented]-ray source

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 The first measurement of the [Formula Presented] analyzing power near threshold has been performed using the High-Intensity Gamma-ray Source (HIGS) at the Duke Free-Electron Laser Laboratory. A 3.58 MeV [Formula Presented]-ray beam having an energy resolut ... Full text Cite

Proton decay following the transfer reaction (7Li, 6He) on 40Ca and 90Zr

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 The charged particle decay of continuum states excited by the single proton stripping reaction (7Li, 6He) at a bombarding energy of 50 MeV/nucleon on targets of 40Ca and 90Zr was measured and compared with theoretical predictions. The results suggest that ... Full text Cite

The 11B(p→,γ)12C reaction below 100 keV

Journal Article Physical Review C - Nuclear Physics · January 1, 2000 The 11B(p→,γ)12C reaction was studied by measuring the γ rays that were produced when 80-100-keV polarized protons were stopped in a thick 11B target. Cross sections and vector analyzing powers at 90° were determined as a function of energy for capture to ... Full text Cite

"A New Photodisintegration Threshold Observable in 3He"

Journal Article Phys. Rev. (Rapid Communications) · 1999 Cite

Proton scattering from the unstable neutron-rich nucleus 43Ar

Journal Article Physical Review C - Nuclear Physics · January 1, 1999 The neutron-rich argon isotope 43Ar has been studied by quasielastic and inelastic proton scattering performed in inverse kinematics. The measured inelastic angular distribution for the second excited state is in good agreement with an L = 2 transition. As ... Full text Cite

Proton scattering by short lived sulfur isotopes

Journal Article Physical Review C - Nuclear Physics · January 1, 1999 Elastic and inelastic proton scattering has been measured in inverse kinematics on the unstable nucleus 40S. A phenomenological distorted wave Born approximation analysis yields a quadrupole deformation parameter β2 = 0.35±0.05 for the 2+1 state. Consisten ... Full text Cite

Spin parity of the 7.478 MeV state of [Formula Presented] and the S factor of the [Formula Presented] reaction

Journal Article Physical Review C - Nuclear Physics · January 1, 1999 Polarized protons were used to measure the analyzing power of [Formula Presented] reaction for [Formula Presented] The analyzing power for the ground state transition compared to calculations leads to a spin-parity assignment of [Formula Presented] for the ... Full text Cite

Population of [Formula Presented] by fragmentation

Journal Article Physical Review C - Nuclear Physics · January 1, 1999 The decay structure of the particle-unstable nucleus [Formula Presented] was studied using the method of sequential neutron decay spectroscopy (SNDS) at 0°. The decay energies of [Formula Presented] can be derived from the relative velocity spectrum of the ... Full text Cite

Energy levels of light nuclei, A=20

Journal Article Nuclear Physics A · June 1998 Cite

Proton decay of states in [Formula Presented]

Journal Article Physical Review C - Nuclear Physics · January 1, 1998 The proton-unbound nucleus [Formula Presented] has been studied via kinematic reconstruction of the emitted proton in coincidence with the residual [Formula Presented] daughter nucleus. Resonances in [Formula Presented] were populated by using a 40 MeV/nuc ... Full text Cite

Elastic and inelastic scattering of protons on 38S in inverse kinematics

Journal Article Nuclear Physics A · April 14, 1997 Elastic and inelastic scattering of protons on unstable 38S nuclei has been measured in inverse kinematics by using a 38S secondary beam at 39 MeV/nucleon. The excitation energy spectrum is measured up to 5 MeV. The first 2+ state is seen at 1.2 MeV excita ... Full text Cite

The effect of a limited acceptance when measuring fragment momentum distributions from halo nuclei

Journal Article Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment · February 21, 1997 Momentum distributions of breakup fragments from halo nuclei are useful to test models for halo nuclei and to estimate the extent of the halo. When breakup fragments are emitted with a non-Gaussian distribution an incomplete acceptance can influence the sh ... Full text Cite

Proton scattering on the unstable [Formula Presented] nucleus: Isovector contribution to the [Formula Presented] state

Journal Article Physical Review C - Nuclear Physics · January 1, 1997 A 39[Formula Presented] MeV [Formula Presented] radioactive beam was used with inverse kinematics to measure angular distributions for elastic and inelastic proton scattering from a [Formula Presented] target. Optical potential and folding model calculatio ... Full text Cite

Upper limit of the lifetime of 16B

Journal Article Physical Review C - Nuclear Physics · January 1, 1996 The lifetime of the neutron-unstable nucleus 16B was investigated to search for evidence of delayed neutron emission (neutron radioactivity). The lifetime was inferred to be less than 191 ps (68% C.L.) based upon the lack of 16B fragments observed in the f ... Full text Cite

New search for 26O

Journal Article Physical Review C - Nuclear Physics · January 1, 1996 An attempt was made to find the very neutron-rich isotope 26O among the fragmentation products of a 90 MeV/nucleon 40Ar beam. This isotope has been predicted to be bound but was not observed in a previous experiment by Guillemaud-Mueller et al. As part of ... Full text Cite

Measurement of the 1H(6He,6Li)n reaction in inverse kinematics

Journal Article Physical Review C - Nuclear Physics · January 1, 1996 The 1H(6He,6Li)n reaction was studied at 0° with the NSCL A1200 fragment separator in the energy loss mode. A 6He secondary beam at E/A =93 MeV was used to measure the Gamow-Teller and Fermi strengths between the ground state of 6He and the ground and exci ... Full text Cite

Study of the breakup reaction 8B→7Be + p: Absorption effects and E2 strength

Journal Article Physical Review Letters · January 1, 1996 Distributions of parallel and transverse momenta for 7Be fragments formed in the breakup of 8B have been measured at 41A MeV. The p‖ distributions are narrow (81+/-4 and 62+/-3 MeV/c FWHM for Be and Au targets, respectively), comparable to those of neutron ... Full text Cite

First study of heavy-ion mirror charge exchange

Journal Article Physical Review Letters · January 1, 1996 Differential cross sections have been measured near 0° for the dominant channels in the mirror reaction 13C(13N,13C)13N at E/A = 57 and 105 MeV. The cross sections of the peaks in the excitation spectrum are discussed in terms of Gamow-Teller and Fermi tra ... Full text Cite

Search for double Gamow-Teller strength by heavy-ion double charge exchange

Journal Article Physics Letters B · November 9, 1995 We have carried out a search for double Gamow-Teller excitations, employing the 24Mg(18O,18Ne)24Ne reaction at 100 and 76 MeV/nucleon at NSCL-MSU and GANIL, respectively. The cross sections for low-lying excitations are typically a few nb/sr, providing evi ... Full text Cite

Studies of light nuclei beyond the particle driplines: the two-proton emitter 12O

Journal Article Nuclear Inst. and Methods in Physics Research, B · May 5, 1995 The decay dynamics of the ground state two proton emitter 12O, which lies beyond the proton dripline, were investigated following the population of 12O via single-neutron stripping of an 13O projectile. The decay products, two protons and 10C, were detecte ... Full text Cite

Evidence for a proton halo in B8: Enhanced total reaction cross sections at 20 to 60 MeV/nucleon

Journal Article Physical Review C · January 1, 1995 Total reaction cross sections R for B8, C12, and N14 on Sinat were measured from about 20 to 60 MeV/nucleon. The R for C12 and N14 compared reasonably well with conventional strong absorption and microscopic calculations. Measured R for B8 were slightly la ... Full text Cite

Projectilelike fragment momentum distributions from Kr86+Al at 70 MeV/nucleon

Journal Article Physical Review C · January 1, 1995 Projectilelike residue yields and momentum distributions from the reaction of 70 MeV/nucleon Kr86 with Al27 at 0°were studied. The data is compared with a model developed originally for higher energies (>200 MeV/nucleon), data from prior experiments perfor ... Full text Cite

One-neutron halo of 19C

Journal Article Physical Review Letters · January 1, 1995 We have measured the longitudinal momentum distribution of 18C, 17C, and 16C after the one-neutron breakup of C19, 18C, and 17C, respectively, using the A1200 fragment separator as an energy-loss spectrometer. The observed narrow width of 44.35.9 MeV/c for ... Full text Cite

Parallel momentum distributions as a probe of halo wave functions

Journal Article Physical Review Letters · January 1, 1995 Distributions of the parallel momentum of Be10 fragments from the breakup of 63A MeV Be11 have been measured for Be9, Nb93, Ta181, and U238 targets. The distributions have similar narrow widths with a mean value of 43.6 1.1 MeV/c FWHM, and agree with a the ... Full text Cite

Momentum distributions of Li9 fragments from the breakup of Li11 and the neutron halo

Journal Article Physical Review C · January 1, 1995 The inclusive parallel momentum distributions of Li9 fragments from the breakup of a secondary Li11 beam have been measured at 66 MeV/nucleon over a wide range of targets (9Be to U238). The measurements were performed using a zero-degree fragment separator ... Full text Cite

Two-proton emission from the ground state of O12

Journal Article Physical Review Letters · January 1, 1995 The three-body decay O12→2p+C10 was studied following production via single-neutron stripping from a radioactive O13 projectile. This is the first observation of two-proton emission from an unbound ground state where the one-proton emission channel is ener ... Full text Cite

Low-lying structure of Li10 in the reaction B11(7Li,8B)10Li

Journal Article Physical Review C · January 1, 1994 Momentum spectra have been measured for the reaction B11(7Li,8B)10Li at 130 MeV and laboratory angles of 5°and 3.5°. There is strong evidence for the existence of a broad state in the unstable nucleus Li10, corresponding to a single p-wave neutron resonanc ... Full text Cite

Quasielastic scattering of Be12,14 on C12

Journal Article Physical Review C · January 1, 1994 The quasielastic scattering of the exotic neutron-drip-line nucleus Be14 on a C12 target has been studied at an incident energy of 796 MeV, and compared with that of the Be12 "core" at the same energy per nucleon. Evidence is presented that the phenomenolo ... Full text Cite

Strong isomer production in fragmentation reactions

Journal Article Physics Letters B · July 29, 1993 The population of the 0+ 0.228 MeV isomer of 26Al has been measured in projectile fragmentation reactions at E/A = 65, 80, and 100 MeV. For beams of 27Al and 28Si, the yield of the isomer was found to be approximately equal to that of the ground state, whe ... Full text Cite

Persistent self-organization of sandpiles

Journal Article Physical Review E · January 1, 1993 We have studied the avalanche fluctuations resulting from the grain-by-grain quiescent perturbation of real sandpiles of various sizes. Contrary to previous reports, we find the attribute of self-organization, namely, a power-law distribution of avalanche ... Full text Cite

Momentum distributions for Be12,14 fragmentation

Journal Article Physical Review C · January 1, 1993 Data on the fragmentation of Be12,14 on C12 at 56 and 65 MeV per nucleon have been obtained. The Be12 fragments from the breakup of Be14 display both a narrow longitudinal momentum distribution and a distinctive angular distribution that is consistent with ... Full text Cite

Neutron decay of Li10 produced by fragmentation

Journal Article Physical Review C · January 1, 1993 The neutron decay of Li10, produced in the reaction of 80 MeV/nucleon O18 + Cnat, was studied by the coincidence detection of neutrons and Li9 nuclei in a collinear geometry. An analysis of the relative velocity spectrum indicates the presence of a Li10 st ... Full text Cite

Mass of Li11 from the C14(B11,Li11)O14 reaction

Journal Article Physical Review Letters · January 1, 1993 The mass of the nucleus Li11 has been determined from a measurement of the Q value of the reaction C14(B11,Li11)O14 at EA32 MeV. The results, which indicate a two-neutron separation energy of S2n(Li11)=295±35 keV, put this basic quantity on a firm basis fo ... Full text Cite

Momentum distributions of Li9 fragments following the breakup of Li11

Journal Article Physical Review Letters · January 1, 1992 A new method, use of a fragment separator as an energy-loss spectrometer, has been developed and used to make the first measurements of the parallel momentum distributions of Li9 nuclei produced in the breakup of Li11. Measurements were made for 66-MeV/nuc ... Full text Cite