Gregory Matousek

The study of quantum chromodynamics (QCD), one of science’s most pressing endeavors, seeks to unlock the mysteries of matter on the infinitesi- mal scale. With QCD, we attempt to understand the complex quark-gluon dynamics of a proton. These theoretical ideas, however, must be tested experimentally. Deeply virtual meson production (DVMP) is a type of particle collision which is ex- tremely sensitive to the proton’s gluon spatial dis- tribution, leading to its analysis becoming a focal point for a future Electron Ion Collider (EIC) exper- iment. This study’s purpose is to demonstrate the precision of DVMP identification for the currently proposed EIC detector system, and to evaluate the system’s capability for capturing the intricacies of the proton structure.

The study of quantum chromodynamics (QCD), one of science’s most pressing endeavors, seeks to unlock the mysteries of matter on the infinitesi- mal scale. With QCD, we attempt to understand the complex quark-gluon dynamics of a proton. These theoretical ideas, however, must be tested experimentally. Deeply virtual meson production (DVMP) is a type of particle collision which is ex- tremely sensitive to the proton’s gluon spatial dis- tribution, leading to its analysis becoming a focal point for a future Electron Ion Collider (EIC) exper- iment. This study’s purpose is to demonstrate the precision of DVMP identification for the currently proposed EIC detector system, and to evaluate the system’s capability for capturing the intricacies of the proton structure.

An electron-proton collision creates particles with mass on the order of 10^(−28) kilograms, and to probe the internal structure of the proton we need to unambiguously identify these particles. By determining the type of particle produced we know if the electron interacted with a valence or sea quark within the proton, which tells us about its quark distribution. A ring-imaging Cherenkov (RICH) detector can identify particles by measuring particle velocities using radiated Cherenkov light, produced when a particle travels faster than the speed of light in a medium. If its momentum is also known, we can effectively “weigh" the outgoing particle, uniquely identifying the particle by its mass.

The Time Projection Chamber (TPC) of sPHENIX, the new experiment at RHIC/BNL, and the PREX/CREX experiment at Thomas Jefferson National Laboratory use Gas Electron Multipliers (GEMs) to amplify the ionization signals from charged particles passing through its gas volume. We have assembled a test setup using two GEM foils backed with a readout plane inside a small gas volume. We present the status and progress in commissioning and testing the system with directly induced charges and an Iron-55 source.