RHIC Spin Physics M. Grosse Perdekamp (University of Illinois and RBRC) Workshop on Hadron Structure and Hadron Spectroscopy August 1-3, 2005 Charles University, Prague RHIC Spin Overview2 August 2 nd Overview o Scientific motivation Proton spin structure G, q/q, q from QCD analysis of polarized proton-proton collisions o Novel experimental tool Polarized proton-proton collisions at high energies The experiments New from run 2005 o Initial results and outlook Helicity distributions Transverse spin physics W-physics and upgrades RHIC Spin Overview3 August 2 nd Structure of the Basic Building Blocks of Matter vs Fundamental Forces in Nature fundamental bound state of matter interaction between the constituents of the bound state measurements with new tools + better precision theory predictions increasingly quantitative RHIC Spin Overview4 August 2 nd Structure of the Basic Building Blocks of Matter vs Fundamental Forces in Nature hydrogen atom Quantum Electro Dynamics Doppler free saturation spectroscopy Lamb shift Example: Lamb Shift (1947) QED pioneers QFT! Tomonaga, Feynman, Schwinger Lamb RHIC Spin Overview5 August 2 nd Structure of the Basic Building Blocks of Matter vs Fundamental Forces in Nature Nucleon Quantum Chromo Dynamics DIS quark structure Friedman, Kendall, Taylor Gell Mann Nakano, Nishijima Nucleon structure: DIS/QCD RHIC Spin Overview6 August 2 nd Structure of the Basic Building Blocks of Matter vs Fundamental Forces in Nature Nucleon Quantum Chromo Dynamics DIS with polarized beams and targets quark helicity dis. Bjorken sum rule RHIC Spin Overview7 August 2 nd Proton Spin Structure in DIS Parton Distribution functions (PDF): Helicity average distribution quarks q(x) : well known gluons G(x) : moderately well known Helicity difference distribution quarks q(x) : moderately well known gluons G(x) : unknown Helicity flip (transversity) distribution quarks q(x) : unknown Field started with polarized source and targets about 1975 Yale/SLAC collaboration 1975 2005 SLAC: E80, E130, E142, E143, E154, E155 CERN: EMC, SMC, COMPASS DESY: HERMES JLab : Halls A,B,C Future progress on G(x), the flavor separation of q(x) and q(x) in DIS appears best possible at future polarized high luminosity e-p collider RHIC Spin Overview August 2 nd AGS LINAC BOOSTER Polarized Source Spin Rotators Partial Snake Siberian Snakes 200 MeV Polarimeter AGS Internal Polarimeter Rf Dipole RHIC pC Polarimeters Absolute Polarimeter (H jet) P HENIX P HOBOS B RAHMS & PP2PP S TAR Siberian Snakes Run 04 P b ~45%, 55 bunches Run 05 AGS pC Polarimeter Helical Partial Snake Strong Snake Spin Flipper = 45% strong AGS snake installed *Complete* A novel experimental method A novel experimental method: Probing Proton Spin Structure in High Energy Polarized Proton Collisions at RHIC RHIC Spin Overview9 August 2 nd Gluon polarization Flavor separation of quark polarizations Transverse spin struc- ture of the Nucleon available channels Inclusive jets, hadrons, photons and heavy flavor production Single lepton asymmetries A L (e,) in W-production (1) A TT with Collins- and Interfe- rence-FFs (2) A N + back-to-back correlations (3) A TT and A T In Drell Yan goals determine first moment of the spin dependent gluon Distribution. flavor separation of quark and anti-quark spin distributions measurements of Collins and Sivers distributions Proton Spin Structure in Polarized p-p Collisions in PHENIX RHIC Spin Overview10 August 2 nd G from a global NLO pQCD Analysis with projected future Direct Photon Data at 200 GeV from RHIC AAC Preliminary M. Hirai, H.Kobayashi, M. Miyama et al. Does NLO pQCD provide a reliable framework for the interpretation of polarized proton data in terms of polarized parton distribution functions? RHIC Spin Overview11 August 2 nd I) Can one extract G(x,Q 2 ) from pp? II) NLO pQCD vs RHIC data Is pQCD applicable at RHIC? RHIC Spin Overview12 August 2 nd Global QCD Analysis for G(x,Q 2 ) and q(x,Q 2 ): J. Pumplin et.al JEHP 0207:012 (2002) x gluon down up-quarks anti-down Quark and Gluon Distributions error on G(x,Q 2 ) error for u(x,Q 2 ) +/- 10% +/- 5% error for d(x,Q 2 ) x CTEQ6: use DGLAP Q 2 -evolution of quark and gluon distributions to extract q(x,Q 2 ) and G(x,Q 2 ) from global fit to data sets at different scales Q 2. H1 + Zeus F 2 CDF + D0 Jets CTEQ5M1 CTEQ6M RHIC Spin Overview13 August 2 nd G(x,Q 2 ) and q(x,Q 2 ) + pQCD beautifully agree Tevatron + HERA! J. Pumplin et.al JEHP 0207:012 (2002) D0 Jet Cross Section ZEUS F 2 RHIC Spin Overview14 August 2 nd and at RHIC ? q(x,Q 2 ), G(x,Q 2 ) and D(z,Q 2 ) + pQCD are nicely consistent with experiment! o Good agreement between NLO pQCD calculations and experiment can use a NLO pQCD analysis to extract spin dependent quark and gluon distributions from RHIC data! PHENIX 0 cross section a ||