Reconstruction of neutral-triggered charged recoil jets in √ s = 200 GeV p+p collisions at the STAR experiment

摘要

Jets — collimated sprays of hadrons — are produced by hard-scattered partons during the early stages of heavy ion collisions. Hence, they provide a valuable probe of the complex multi-particle dynamics within the hot, dense medium produced in such collisions. In particular, the study of jets recoiling from direct photons (γ_(dir)+jet) and those recoiling from energetic π~(0)(π~(0)+jet) may shed light on the path-length and initial flavor (quark vs. gluon) dependence of the energy-loss experienced by a parton as it traverses the medium. We present here measurements of the yields of charged recoil jets tagged by γ_(dir)and π~(0)in p+p collisions at √ S = 200 GeV. These measurements will serve as a vacuum fragmentation reference for an upcoming measurement in Au + Au collisions.