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Heavy Ions Collisions (results and questions) PART II. Anatoly Litvinenko. litvin@moonhe.jinr.ru. 1. Some estimations. 2. Particle ratios and s tatistical models. 3. 3. Particle (hadrons) spectra. A Iordanova (for the STAR Collaboration) ; J. Phys. G35 , p. 044008 , (2008. 4. 4.
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Heavy Ions Collisions (results and questions) PART II Anatoly Litvinenko litvin@moonhe.jinr.ru 1
Particle (hadrons) spectra A Iordanova (for the STAR Collaboration);J. Phys. G35, p.044008, (2008 4 4
QUESTION II Is equilibrium state of hot and dense hadronic matter achieved? What is the conclusion about it from experiment? The strong indication that YES.
Observables and hadronic matter properties Some designations sQGP for strongly-interacting Quark-Gluon Plasma Commonly accepted: QGP, pQGP,wQGP for weakly-interacting Quark-Gluon Plasma
Baryons Mesons Phys. Rev. Lett. 98, 162301 (2007) KET – CQN Scaling Quark-Like Degrees of Freedom Evident Roy A. Lacey, Stony Brook; Quark Matter 09, Knoxville, TN March 30 - April 4, 2009 10
Elliptic flow – energy dependance K. Aamodt et al.(ALICE Collaboration), PRL 105, 252302 (2010) 11
JET Quenching Jet: A localized collection of hadrons which come from a fragmenting parton Modification of Jet property in AA collisions, because of partons propagating in colored matter, which lose energy. One of the possible observable Was predicted in a lot of works. Some of them (not all) are: • J.D.Bjorken (1982), Fermilab – PUB – 82 – 059 - THY. • M.Gyulassy and M.Palmer, Phys.Lett.,B243,432,1990. • X.-N.Wang, M.Gyulassy and M.Palmer, Phys.Rev.,D51,3436,1995. • R.Baier et al., Phys.Lett.,B243,432,1997. • R.Baier et al., Nucl.Phys.,A661,205,1999 12
High pT (> ~2.0 GeV/c) hadrons in NN h d h Parton distribution functions a b c Hard-scattering cross-section h h Fragmentation Function
High pT (> ~2.0 GeV/c) hadrons in AA Parton distribution functions h Hard-scattering cross-section A B Fragmentation Function + Numbers of binary collisions Partonic Energy Loss h
Suppression of high-pt hadrons. Qualitatively. Nuclear modification factor From naive picture is what we get divided by what we expect. 15 15
Nuclear modification factor Normalization on peripheral collisions 16 16
First data in first RHIC RUN Jet Quenching ! Great! But (see the next slide) 17
Nuclear modifications to hard scattering Large Cronin effect at SPS and ISR Suppression at RHIC Is the suppression due to the medium? (initial or final state effect?) 18
Au+Au @ sNN = 200 GeV Au+Au @ sNN = 200 GeV Au+Au @ sNN = 200 GeV Au+Au @ sNN = 200 GeV d+Au @ sNN = 200 GeV d+Au @ sNN = 200 GeV d+Au @ sNN = 200 GeV d+Au @ sNN = 200 GeV preliminary preliminary preliminary preliminary Again Au+Au and d+Au • Nice picture! Isn’t it? 20
The matter is so opaque that even a 20 GeV p0 is stopped. Suppression is very strong (RAA=0.2!) and flat up to 20 GeV/c Common suppression for p0 and h; it is at partonic level e > 15 GeV/fm3; dNg/dy > 1100 21
JET Quenching at LHC .ALICE Collaboration, Physics Letters B 696 (2011) 30 .
JET Quenching at LHC ALICE Collaboration, Physics Letters B 696 (2011) 30
The matter is so dense that even heavy quarks are stopped Even heavy quark (charm) suffers substantial energy loss in the matter The data provides a strong constraint on the energy loss models. The data suggest large c-quark-medium cross section; evidence for strongly coupled QGP? (1) q_hat = 0 GeV2/fm (4) dNg / dy = 1000 (2) q_hat = 4 GeV2/fm (3) q_hat = 14 GeV2/fm 24
Trigger particle Near side jet Away side jet If there are any other observables for Jet Quenching? Yes! Back to Back Jets correlation. Associated particles Correlation of trigger particles 4<pT<6.5 GeV withassociated particles 2<pT<pT,trig 25
Back to Back Jets correlation. Dependence from reaction plane. Out-of-plane In-plane In-plane Out-of-plane 26
STAR Preliminry 20-60% 20-60% Jet tomography Out-plane Back-to-back suppression depends on the reaction plane orientation In-plane energy loss dependence on the path length! 27
The matter is so dense that it modifies the shape of jets The shapes of jets are modified by the matter. Mach cone? Cerenkov? Can the properties of the matter be measured from the shape? Sound velocity Di-electric constant Di-jet tomography is a powerful tool to probe the matter 28
One more results from lattice QCD heavy-quark screening mass -- suppression In EM plasma it is well known Debye screening 30
The matter is so dense that it melts(?) J/y (and regenerates it ?) J/y’s are clearly suppressed beyond the cold nuclear matter effect The preliminary data are consistent with the predicted suppression + re-generation at the energy density of RHIC collisions. Can be tested by v2(J/y)? dAu mm 200 GeV/c AuAu mm 200 GeV/c CuCu mm 200 GeV/c AuAu ee 200 GeV/c CuCu ee 200 GeV/c 31
direct photons • T0max ~ 500-600 MeV !? • T0ave ~ 300-400 MeV !? 33 33
Summary • RHIC has produced a strongly interacting, • partonic state of dense matter 34
(1) q_hat = 0 GeV2/fm (4) dNg / dy = 1000 (2) q_hat = 4 GeV2/fm (3) q_hat = 14 GeV2/fm Summary • The matter is so dense that even heavy quarks are stopped 35
Summary • The matter is so strongly coupled • that even heavy quarks flow 36
Summary • The matter is so dense that it melts(?) • J/y (and regenerates it ?) 37
Summary • The matter modifies jets 38
Put the results together The matter is strongly coupled The matter is dense • > 15 GeV/fm3 dNg/dy > 1100 Tave = 300 - 400 MeV (?) PHENIX preliminary The matter modifies jets The matter may melt but regenerate J/y’s 39 39 The matter is hot
Modeling the Source Interaction region Assembly of classical boson emitting sources in space-time region The source S(x,p) is the probability boson with p is emitted from x Determines single-particle momentum spectrum E d3N/dp3 = d4x S(x,p) Determines the HBT two-particle correlation function C(K,q) C(K,q) ~ 1 + | d4x S(x,K) exp(iq·x) | 2/| d4x S(x,K) |2 where K = ½(p1 + p2) = (KT, KL), q = p1 – p2 The LCMS frame is used (KL = 0) In the hydrodynamics-based parameterizations: assume something about the source S(x,p) Gaussian particle density distribution Linear flow (rapidity or velocity) profile Instantaneous freeze-out at constant proper time (“sharp”) January 6, 2002 RHIC/INT Winter Workshop 2002 45
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Why the collisons of heavy nuclei is interesting? Let us see on the space – time picture of collision pre-collision QGP (?) and parton production hadron reinteraction hadron production QCD phase diagram 49 49