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The 31 st International Symposium on Multiparticle Dynamics on 1-7, Sept. 2001 in Datong, China. Correlation and fluctuation studies at RHIC. Toru Sugitate Hiroshima University Sugitate@hepl.hiroshima-u.ac.jp. Temperature. quark confinement. Chiral symmetry. Quark-Gluon Plasma.
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Toru Sugitate / Hiroshima Univ. • The 31st International Symposium on • Multiparticle Dynamics • on 1-7, Sept. 2001 • in Datong, China Correlation and fluctuation studies at RHIC Toru Sugitate Hiroshima University Sugitate@hepl.hiroshima-u.ac.jp
Temperature quark confinement Chiral symmetry Quark-Gluon Plasma Baryon density Hadronic Matter Normal Nucleus Multiparticle dynamics in high-energy heavy-ion collisions Toru Sugitate / Hiroshima Univ. Relativistic Heavy Ion Collider (RHIC) begins smashing atoms at sNN = 200 GeV. Experiments will yield insights into the structure of matter and how the universe evolved. Understand the non-pertuabative QCD nature; multiparticle dynamics of deconfined quarks and gluons in Quark-Gluon-Plasma, which probably existed in the early Universe.
In the 1st order phase transition, matter of the mixed phases stops expansion due to the softening of Equation of State. Consequently a prolonged lifetime of particle emission is expected. In the Longitudinal Center of Mass System (p1z+p2z=0); QGP B It is obvious for a static source, but our source is expanding.. TC T Particle correlations – a tool to pin down the phase transition Toru Sugitate / Hiroshima Univ.
d p K STAR Acceptance e The STAR (Solenoidal Tracker atRHIC) experiment at RHIC Toru Sugitate / Hiroshima Univ. • A large volume TPC covers || < 1 with a full azimuthal coverage. • PID capability of TPC - dE/dx and RICH. • Topological PID technique for short lived and/or neutral particles.
The PHENIX (Pioneering High Energy Nuclear Interaction eXperiment)at RHIC Toru Sugitate / Hiroshima Univ. Broadest possible study of A-A, p-A, p-p collisions to • study nuclear matter under extreme conditions using a wide variety of probes sensitive to all timescales, i.e., hadrons, electron, muons, and photons as many potential signatures of QGP as possible, and • study systematic variations with species and energy. Measure spin structure of the nucleon.
Q Long Q Side Q Out C2 (Q; Qothers< 80 MeV/c) PHENIX preliminary for QM01 Q ( MeV/c) Q ( MeV/c) Q ( MeV/c) Negative pion correlation studies in STAR and PHENIX Toru Sugitate / Hiroshima Univ. 12-15% most central events in Au+Au at sNN=130 GeV. Negative pions in the mid-rapidity. 3 dimensional analysis in the LCMS frame. STAR published in PRL 87(2001)082301 • First particle correlation data at RHIC. • Consistent between two experiments. • Positive pions show similar results. • No surprise with the C2 functions.
1.2 4 1 (Rout2-Rside2) 2 0.8 0.6 0 0.4 8 8 8 1.5 Rout/Rside 6 6 6 1 Rout (fm) 4 4 4 0.5 1 100 10 sNN (GeV) Rside (fm) Rlong (fm) 2 1 10 100 sNN (GeV) s dependence of source size parameters viewed by negative pions Toru Sugitate / Hiroshima Univ. E895 NA44 NA49 PHENIX E866 WA98 STAR • No significant rise or jump from AGS to RHIC. • Parameters are quite similar to those at SPS. • Transverse radii seems to be constant. • Longitudinal radius increases as s. • No remarkable difference between Rout and Rside. • is similar to those at SPS/AGS. • No indication of a long-lived mixed phase.
NA44 published in PRL 87(2001)112301 1.2 + - + - STAR published data in PRL87 (2001)082301 1.0 0.8 0.6 0.4 R=3.0 / mT 8 8 6 6 Rout (fm) Rout (fm) 4 4 8 8 6 6 Rside (fm) Rside (fm) 4 4 8 8 6 6 Rlong (fm) Rlong (fm) 4 4 2 2 low low high high 0.3 0.3 0.2 0.2 med med 0.4 0.4 Does the mT scaling observed at SPS explain the present RTrans and RLong data at RHIC ? centrality bin centrality bin mT (GeV/c2) mT (GeV/c2) Centrality and mT dependences of the source size parameter Toru Sugitate / Hiroshima Univ. • + and -show same dependences. • ’s do not change with multiplicity, but • R’s increase with centrality. • consistent with native expectation of geometrical size. • ’s increase, but R’sdecrease as mT. • consistent with a hypothesis of hydrodynamical expanding sources.
Fluctuation of locally conserved quantities; net baryon number, electric charge, strangeness prove the quark de-confinement phase. M. Asakawa presented in QM01; The Net Baryon number in hadron gas The net Baryon number in a QGP with 2 massless flavor Then, we should see difference in; and Fluctuations – a tool to pin down the phase transition Toru Sugitate / Hiroshima Univ.
<Pt> , Central Collisions PHENIX Preliminary Centrality: 0-5% Datavs. Mixed Event <Pt> (GeV/c) Gamma Distribution Calculation Note: This is not a fit! M. Tannenbaum, Phys. Lett. B498 (2001) 29. <Pt> (GeV/c) Event-by-event fluctuations in the mean Pt in PHENIX Toru Sugitate / Hiroshima Univ. by J. Mitchell(BNL) for the ACS on 8/30/01
<Et> , Central Collisions Mean Max Simulation Centrality: 0-5% PHENIX Preliminary PbSc <Et> (GeV) Event-by-event fluctuations in the mean Et in PHENIX Toru Sugitate / Hiroshima Univ. Simulation for statistically independent emission incl. experimental biases. by J. Mitchell(BNL) for the ACS on 8/30/01
Hydrodynamic QGP fluid + hadronic re-scattering; S.Soff, A.Bass, A.Dumitru, PRL 86 (2001) 3981 Summary and outlook of correlation and fluctuation studies at RHIC Toru Sugitate / Hiroshima Univ. • The source size parameters at sNN = 130 GeV are similar to those at SPS/AGS. • The duration time is consistent with zero, similar to those at SPS/AGS. • No indications of a huge source formation or a prolonged mixed phase. • No significant non-statistical fluctuations in <pT> and <ET> were seen by PHENIX, but some indication in charge independent <pT> by STAR. • Why all the source sizes are almost constant in about two orders of s? • No QGP’s? What controls the source size parameters? • Why the mT scaling at SPS explains the radii at RHIC? Is there any universal scaling on s? Another hint; RLong ~ RTrans at both SPS and RHIC. • Why almost no duration time during pion emissions? Did hydrodynamical flow wash out the signals? • Look at Au+Au at sNN = 200 GeV. • Study the correlation functions by other particle species. • Study the net baryon-, charge- and strangenss-fluctuations. • Event-by-Event correlation and fluctuation. • Energy scan and different collision systems.