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A LL for QGC scattering interpreted in LO QCD :. Gluon polarization. pQCD result for QGC scattering. Measured polarized/unpolarized structure function. Proton Spin. Gluon Spin. Orbital Motion. Quark Spin.
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ALL for QGC scattering interpreted in LO QCD: Gluon polarization pQCD result for QGC scattering Measured polarized/unpolarized structure function Proton Spin Gluon Spin Orbital Motion Quark Spin Određivanje gluonskog doprinosa spinu protona STAR detektorom na RHIC (Relativistic Heavy Ion Collider)-u M. Planinić, M. Furić i D. Androić PMF, Zagreb, Hrvatska i STAR kolaboracija (40-tak institucija) Brazil: Universidade de Sao Paulo China: IHEP – Beijing IMP - Lanzou IPP – Wuhan USTC SINR – Shanghai Tsinghua University Great Britain: University of Birmingham France: IReS Strasbourg SUBATECH - Nantes Germany: MPI – Munich University of Frankfurt India: IOP - Bhubaneswar VECC - Calcutta Panjab University University of Rajasthan Jammu University IIT - Bombay VECC – Kolcata Poland: Warsaw University of Tech. Croatia: Univesity of Zagreb Russia: MEPHI - Moscow LPP/LHE JINR - Dubna IHEP - Protvino U.S. Laboratories: Argonne Berkeley Brookhaven U.S. Universities: UC Berkeley UC Davis UC Los Angeles Carnegie Mellon Creighton University Indiana University Kent State University Michigan State University City College of New York Ohio State University Penn. State University Purdue University Rice University Texas A&M UT Austin U. of Washington Wayne State University Yale University STAR kolaboracija • Motivacija: • Razumjeti strukturu nukleona !!! • Ispitivanje doprinosa gluona i kvarkova mora nukleonskim svojstvima (osim mase). • Da li se ta svojstva mogu modelirati valentnim kvarkovima ? • Eksperimenti duboko neelastičnog raspršenjaspinovi kvarkova i antikvarkova doprinose ~30% spinu nukleona . • Gluonski spinski doprinos može se istražiti u procesima s jakim međudjelovanjem. • RHIC-ovi polarizirani (sudarajući) protonski snopovi su na energijama gdje PQCD može opisati tvrde sudare. Zašto je zanimljivo mjeriti gluonski doprinos spinu protona? Zagreb je član kolaboracije ! Polarizirani snopovi protona naRHIC-u Kako ćemo mjeriti gluonski doprinos spinu protona? . Mjerenjem ALL možemo odrediti G: Solenoidal Tracker AtRHIC (STAR) Dosadašnji rezultati spinskog programa na RHIC-u: . Prvi rezultati za AN(jednostruka transferzalna spinska asimetrija) p + p p0 + X AN p + p p0 + X Theory predictions at pT=1.5 GeV/c: Collins effect Anselmino, et al., private communication; PRD 60 (1999) 054027. Sivers effect Anselmino, et al., private communication; Phys. Lett. B442 (1998) 470. Twist 3 effectQiu and Sterman, private communication; PRD 59 (1998) 014004. 0.4 STAR FPD Preliminary Data Assuming AN(CNI)= 0.013 pT=1.1 - 2.5 GeV/c s=200 GeV 0.2 0 Ultimately at RHIC, any combination of beam polarization (longitudinal (+/-) /transverse (/)) is possible, which allows to access different parts of the proton spin structure Tragovi čestica u TPC-u (STAR) na Au-Au sudarimapri sNN=130 GeV boje ~ impuls:mali---veliki Syst. Uncer. = ±0.05 -0.2 0 1.0 0.8 0.6 0.2 0.4 xF ~ E / 100 GeV Zainteresirani ? Javite se u sobu 319 ili na e-mail planinic@phy.hr Uzbudljivo vrijeme je pred nama za istraživanje spinske strukture protona na RHIC-u ! Pridružite nam se !