Clocking Hadronization at RHIC Using the Balance Function and STAR

摘要

In the summer of 2000, gold nuclei were collided at (SNN)~(1/2) = 130 GeV at the Relativistic Heavy Ion Collider (RHIC). The analysis focuses on the measurement of balance functions in the Solenoidal Tracker At RHIC (STAR) detector. Balance function calculations of Bass et al. predict that the width of the balance function indicates the time of hadronization of particles formed in a relativistic heavy ion collision. Data analysis is compared to HIJING simulations analyzed through GEANT. The width of the balance function measured for peripheral events is similar to that of HIJING. The balance function narrows as events become more central, which may show that the central collisions contain primarily particles which hadronized later than for peripheral events. Mixed event analysis indicates that this measurement has signal above a statistical background. Pseudorapidity cuts illustrate the effects of balance function measurements made with a smaller detector.