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Kollektive Eigenschaften in Kern-Kern Kollisionen bei hohen Energien

Kollektive Eigenschaften in Kern-Kern Kollisionen bei hohen Energien. Kai Schweda, Physikalisches Institut/ GSI Darmstadt. Quantum Chromodynamics. Quantum Chromodynamics (QCD) is the established theory of strongly interacting matter. Gluons hold quarks together to from hadrons:

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Kollektive Eigenschaften in Kern-Kern Kollisionen bei hohen Energien

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  1. Kollektive Eigenschaftenin Kern-Kern Kollisionen bei hohen Energien Kai Schweda, Physikalisches Institut/ GSI Darmstadt

  2. Quantum Chromodynamics • Quantum Chromodynamics (QCD) is the established theory of strongly interacting matter. • Gluons hold quarks together to from hadrons: • Gluons and quarks, or partons, typically exist in a color singlet state: confinement. meson baryon

  3. LHC RHIC COBE Natur Quark-Gluon Plasma Atome Nukleonen Kerne Heute Urknall 10 –6 sec 10 –4 sec 3 min 15 Mil Jahre Experiment http://www.lbl.gov/Publications/Nobel/ George Smoot John Mather COBE: Discovery `baby photo’ of the universe RHIC: Live history of the universe

  4. Quark Gluon Plasma Source: Michael Turner, National Geographic (1996) • Quark Gluon Plasma: • Deconfined and • thermalized state of quarks and gluons •  Study partonic EOS at RHIC and LHC(?) Probe thermalization using heavy-quarks

  5. STAR Au + Au Collisions at RHIC Peripheral Event (real-time Level 3)

  6. STAR Au + Au Collisions at RHIC Mid-Central Event (real-time Level 3)

  7. STAR Au + Au Collisions at RHIC Central Event (real-time Level 3)

  8. Pressure, Flow, … • Thermodynamic identity • – entropy p – pressure U – energy V – volume t = kBT, thermal energy per dof • In A+A collisions, interactions among constituentsand density distribution lead to: pressure gradient  collective flow • number of degrees of freedom (dof) • Equation of State (EOS) • cumulative – partonic + hadronic

  9. More central collisions Protons From RHIC • In central collisions, spectrum becomes more concave collective flow ! • Flow velocity <b> = 0.60 ± 0.05 in most central collisions

  10. Anisotropy Parameter v2 coordinate-space-anisotropy  momentum-space-anisotropy y py px x Initial/final conditions, EoS, degrees of freedom

  11. v2 at Low Momentum P. Huovinen, private communications, 2004 - Mass hierarchy  collective flow ! - Hydro-dynamical model : acces to equation of state !

  12.  -meson Flow: Partonic Flow • -mesons: • little hadronic interactions • strong collective flow • formed via coalescence of • thermal s-quarks •  Collectivity at quark level ! STAR Preliminary: SQM06, S. Blyth Hwa and Yang, nucl-th/0602024; Chen et al., PRC73 (2006) 044903

  13. Collectivity, Deconfinement at RHIC - v2 of light hadrons and multi-strange hadrons - scaling by the number of quarks At RHIC:  number-of-constituent quark scaling  De-confinement PHENIX: PRL91, 182301(03) STAR: PRL92, 052302(04), 95, 122301(05) nucl-ex/0405022, QM05 S. Voloshin, NPA715, 379(03) Models: Greco et al, PRC68, 034904(03) Chen, Ko, nucl-th/0602025 Nonaka et al. PLB583, 73(04) X. Dong, et al., Phys. Lett. B597, 328(04). i ii

  14. EoS Parameters at RHIC • In central Au+Au collisions at RHIC • - partonic freeze-out: • *Tpfo = 165 ± 10 MeV weak centrality dependence • vpfo ≥ 0.2 (c) • - hadronic freeze-out: • *Tfo = 100 ± 5 (MeV) strong centrality dependence • vfo = 0.6 ± 0.05 (c) • Systematic studies are needed to understand the • centrality dependence of the EoS parameters • * Thermalization assumed

  15. Higgs mass: electro-weak symmetry breaking. (current quark mass) • QCD mass: Chiral symmetry breaking. (constituent quark mass) • Strong interactions do not affect heavy-quark masses. • Important tool for studying properties of the hot/dense medium at RHIC. • Test pQCD predictions at RHIC and LHC. Quark Masses Total quark mass (MeV)

  16. J/yEnhancement at LHC • Statistical hadronization  strong centrality dependence of J\y yield at LHC • Need total charm yields ! • Measure D0, D±, Lc • Probe deconfinement and thermalization J/y: c c  scc Number of participants More central collisions Calculations: P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/0304013.

  17. Multiply Heavy-flavored Hadrons • Statistical hadronization- de-confined heavy-quarks • equilibrated heavy-quarks •  Enhancement up to x1000 ! • Measure Xcc, Wcc, Bc, (Wccc) • Need total charm yields • Probe deconfinement and thermalization @ LHC • Quark Gluon Plasma ! Quarks and gluons  hadrons Pb+Pb Wccc / D : p+p c cc x1000 F. Becattini, Phys. Rev. Lett. 95, 022301 (2005); P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/0304013.

  18. The key point is to idenitfy and measure Heavy-Flavor Collectivity D0, D, D+s, L+C, J/y, B0, B±, , …

  19. Large Hadron Collider LHC am CERN Energie in einer Blei-Blei Kollision 1150 TeV = 0.18 mJ Faktor 300 höher als in SPS Experimenten sehr heisser Feuerball! T = 1000 MeV

  20. ALICE beim LHC Bis zu 60000 geladene Teilchen Faktor 25 höher als beim SPS ~ PetaByte (1015) pro Jahr TRD TPC ITS

  21. J/y  e+ + e- Reconstruction J/y: c c : b b • J/y e+ + e- (BR = 6%) • Reconstruct invariant mass • TRD identifies electrons  Identify quarkonia

  22. Taken from P. Senger 1) LHC heavy-flavor program: 2) FAIR / CBM program: - Study medium properties - pQCD in hot and dense medium - Search for phase boundary. - Chiral symmetry restoration Start: 2007 Start: ~2012

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