Exploring the proton spin : neutron asymmetry as recorded by zero degree calorimeters : an honors thesis (HONRS 499)

The Relativistic Heavy Ion Collider (RHIC) located at the Brookhaven National Laboratory is used to probe the subatomic structure of matter. STAR (Solenoidal Tracker at RHIC) is one of four major detectors positioned at different places around the RHIC ring to observe the collision of two particle beams. Furthermore, one specific project of STAR is to analyze how quark, gluons, and orbital angular momentum contribute to the proton spin. Spin is a particle's intrinsic angular momentum, a property of particles as basic as mass and electrical charge. In addition, by colliding beams of polarized protons, physicists can examine the structure underlying the proton's spin. In order to help advance the understanding of the proton spin, my research focuses on detectors that at very forward positions record the asymmetry of neutrons produced by collisions. As energy levels are increased beyond the level of 250 billion electron volts (GeV), the Zero Degree Calorimeter (ZDC) detector is the only detector that is able to record the asymmetry.