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RHIC/HENP Physics Program: Connections with LANL Theory Mike Leitch – P-25, leitch@lanl.gov Parton structure, modification in nuclei, spin-dependence and the Quark Gluon Plasma(QGP): Flavor asymmetry of the nucleon sea and its spin-dependence; origins from meson-cloud of the nucleon Gluon structure functions, their shadowing in nuclei and spin- dependence Energy loss & fragmentation of partons (light & heavy) in nuclei to elucidate the parton dynamics of these processes. Contrast with same in hot/high-density matter. Heavy-quark (open and closed-c,b) production and suppression in cold nuclei & in QGP. Characteristics of heavy-ion collisions through charged particle multiplicities, reaction plane measurements, etc.
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FNAL E866/NuSea ACU, ANL, FNAL, GSU, IIT, LANL, LSU, NMSU, UNM, ORNL, TAMU, Valpo A measurement of Anti-quark asymmetry in the Nucleon Sea
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E866/NuSea: 800 GeV p-A (Fermilab) PRL 84, 3256 (2000) J/Ψ and Ψ’ similar at large x F where they both correspond to a traversing the nucleus but Ψ’ absorbed more strongly than J/Ψ near mid-rapidity (x F ~ 0) where the resonances are beginning to be hadronized in nucleus. open charm: no A-dep at mid-rapidity Hadronized J/ P T Broadening at 800 GeV (p T ) shape is independent of x F & same for NA3 at a lower energy
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Magnet Muon Identifiers Muon 12.5° 35°35° 10.5° 2 Muon Trackers = 2x3 stations 2x3 stations 2 Muon Identifiers = 2x5 planes South Arm: Began operations in 2001-2002 run. North Arm: Installed in 2002, now running. PHENIX Muon Arms Acceptance : 1.2 < | | < 2.4 Muon minimum momentum ~ 2 GeV/c Tracking Stations
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South Muon Arm North Muon Arm Multiplicity & Vertex Detector
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p+p J/ + - Br (J/ + - ) d J/ /dy| y=1.7. = 37 7 (stat.) 11 (syst.) nb PHENIX Preliminary N J/ = 36 7 (stat.) 4 (syst.) A cc reco = 0.0163 0.031 BBC J/ L = 0.60 0.12 nb -1 y: rapidity coverage = 1.0 p+p s=200GeV
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Raufeisen & Peng hep-ph/0211422 Relating parton model and color dipole formulation of heavy quark hadroproduction PHENIX J/ data from Run-II theoretical uncertainty
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Cooper, Liu, Mottola, Nayak, “Color Octet Contribution to High p T J/ Production in pp Collisions at RHIC” Direct and feed- down J/ production in color-octec and – singlet channels at 200 & 500 GeV
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Analysis of our p-A Drell-Yan data (E772) using the color-dipole model. Dashed lines with shadowing only; solid lines with parton energy loss. dE/dz = -2.73 ± 0.37 GeV/fm Charged hadron and 0 production at PHENIX versus p T for central collisions which, when compared to pQCD models that work well for peripheral collisions, suggests that jet- quenching or energy-loss may be present. dE/dx = 0 dE/dx =0.25 Johnson, Kopeliovich et al. PRL 86, 4483 (2001) Shadowing dE/dx & Shadowing Quark energy loss in nuclear matter dE/dx = 0 dE/dx =0.25 E772 DY data
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Gluon Shadowing – Largely Unknown Kopeliovich, Tarasov, & Hufner hep-ph/0104256 Eskola, Kolhinen, Vogt hep-ph/0104124 PHENIX μ + μ - (Au) Gluon shadowing for J/Ψ’s in PHENIX μ acceptance? Large uncertainty: Eskola… : ~ 0.8 vrs Kopeliovich… : ~ 0.4 Must be measured PHENIX μ PHENIX e E866 (Y~0) Eskola Kopeliovich Shadowing for d+Au -> J/
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Kopeliovich et al hep-ph/0104256 & hep-ph/0205151 with anti-shadowing & EMC without Shadowing more than a factor of two stronger for charmonium production than for open-charm calculation includes absorption/formation time effects & is actually for the 2 ) No EMC Anti-shadowing Whereas ordinary parton model shadowing factorizes and is a “property”of the nuclear structure function Process Dependence of Shadowing
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P T Broadening Raufeisen, hep-ph/0301052 Relating broadening for dipole, BDMPS & higher twist Broadening proportional to average color field strength
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Raufeisen, Peng, Nayak, hep-ph/0204095 Parton model versus color dipole formulation of the Drell-Yan process Approximate equivalence of the two approaches which are thought to represent the same physics, but in different reference frames. E772 & E866 data NLO (parton model) Color dipole model
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