Heavy Ion Physics at NICA V. Toneev Bogoliubov Laboratory of Theoretical Physics CBM meeting, Dubna, May 19, 2009 Phase diagram of QCD matter Goal of high energy heavy-ion physics Study of in-medium properties of hadrons and nuclear matter equation of state including a search for possible signs of deconfinement and/or chiral symmetry restoration phase transitions and QCD critical end-point USA-NSAC Long range plan 2007 NICA Scanning the phase diagram PT is a transitional state PT evolves in finite space/time after PT the system continues to interact Ivanov,Russkikh,Toneev, PR C73 (2006) F-hydro, hadronic EoS V.Toneev and V.Skokov kinetic-hydro hybrid, mixed phase EoS Tentative list of observables in alphabetical order Anti-proton to proton ratio Baryon to meson ratios Charged particle directed flow Charged particle elliptic flow DCC searches Elliptic flow for identified charged hadrons & photons Femtoscopy of identical particles Femtoscopy of K, , , etc Fluctuations of particle ratios, esp. K/, p/ Fluctuations of,, photon multiplicity, etc Hyperons and light hypernuclei Invariant mass and p T distributions of leptons Longe-range forward-backward correlations Net-proton and net charge kurtosis Nuclear modification factor Tentative list of observables, continued Rapidity and p T spectra of identified hadrons Production of light nuclei and antinuclei Standard femtoscopy source parametrs Strange to non-strange ratios for mesons and baryons Strong parity violation Triggered azimuthal correlations Untriggered pair correlation in and Yields of strange particles Yields of various species and statistical model fits Strange to non-strange particle ratio, horn M.Gazdzic ki, arXiv: M.Gazdzicki, M.I.Gorenstein, Acta Phys. Pol. B30 (1999) 2705 NICA Excitation functions of K + / +, K - / - and (+ 0 )/ ratios Experimental K + / + ratios show a peak at ~30 A GeV (horn) which is not reproduced by hadronic transport models HSD and UrQMD E.Bratkvskaya et al., Phys. Rev. C69 (2004) Statistical hadronization model (thermalization?) Braun-Munzinger et al., arXiv: Analysis 2005: horn is not well reproduced Analiysis 2008 Data update -meson Higher res. Transverse temperature, step M.Gazdzicki, arXiv: M.Gazdzicki, M.I.Gorenstein, Acta Phys. Pol. B30 (1999) 2705 NICA Inverse T slopes of K + and K - spectra Phys.Rev. C69 (2004) ; PRL 92 (2004) In HSD and UrQMD hadronic rescattering has only a small impact on the slope of kaon spectra. The hadron-string picture fails ? New degrees of freedom New data from lowRHIC STAR Preliminary L.Kumar for STAR Collaboration, QM2009: Central Au+Au s=9.2 GeV The RHIC results are in agreement with NA49 data and follow the established beam energy trends Hadronic collectivity Yu.Ivanov, V.Russkikh, Eur.Phys.J. A37 (2008) 139 A.Larionov et al., Phys.Rev. C76 (2007) I nclusion of 3-body collisions in a transport code 3-fluid relativistic hydrodynamics Partonic collectivity The hot non-perturbative gluon plasma is almost ideal colored liquid (sQGP) DQPM PHSD W.Cassing, Nucl.Phys. A791 (2007) 365; A795 (2007) 70; W.Cassing, E.L.Bratkovskaya, Phys.Rev. C78 (2008) percolation parameter = N + 2/3 suggests a liquid ! A.Peshier, W.Cassing, PRL 94 (2005) plasma parameter suggests a liquid ! The HOLE-JET transition (high p T ) The azimuthal correlation function: ( central Pb+Pb) NA49: M.Szuba et al., arXiv: Transition at the same energy ! Fluctuations Fluctuations of the quark number density (susceptibility) at B >0 (C.Allton et al., PR D68 (2003) ) Lattice QCD predictions: Fluctuations of the quark number density (susceptibility) at B >0 (C.Allton et al., PR D68 (2003) ) q (quark number density fluctuations) will diverge at the critical end point Experimental observation: Baryon number fluctuations Baryon number fluctuations Charge number fluctuations Charge number fluctuations Particle ratio fluctuations K/ , p/ K/ fluctuations increase towards lower beam energy K/ fluctuations increase towards lower beam energy Significant enhancement of measured ratio over hadronic cascade model UrQMD p/ fluctuations are negative p/ fluctuations are negative indicates a strong contribution from resonance decays NA49 Collaboration. arXiv: Event-by-event transverse momentum and multiplicity fluctuations Energy dependence of p T fluctuations No significant energy dependence at SPS energies. NA49 data do not provide evidence for critical point fluctuations Magnitude of fluctuation at CP with correlation length from Stephanov, Rajagopal, Shuryak, PR D60 (1999) Width of CP region ( B )30, (T)10 MeV based on Hatta, Ikeda PR D67 (2003) CP 1 location: B (CP 1 )=360 MeV, T(CP 1 )147MeV (chemical freeze-out temperature for Pb+Pb at B =360 MeV) Energy dependence of multiplicity fluctuations No significant energy dependence at SPS energies. NA49 data do not provide evidence for critical point fluctuations NA49 Collaboration, arXiv: System size dependence of PT at 158 AGeV Maximum of PT observed for C+C and Si+Si; Increase ~ two times larger for all charged than for negatively charged hadrons. Data are consistent with CP 2 predictions. s 11 GeV ? K.Grebieszkow for the NA49 Collaboration, QM2009 System size dependence of at 158 AGeV Maximum of observed for C+C and Si+Si; Increase ~ two times larger for all charged than for negatively charged hadrons. Data are consistent with CP 2 predictions. Scanning in (A+A) ! K.Grebieszkow for the NA49 Collaboration, QM2009 x z Y Out-of-plane Y X - directed flow - elliptic flow V 2 > 0 indicates in-plane emission of particles V 2 < 0 corresponds to a squeeze-out perpendicular to the reaction plane (out-of-plane emission) Non central Au+Au collisions : interaction between constituents leads to a pressure gradient => spatial asymmetry is converted to an asymmetry in momentum space => collective flow In-plane v 1 and v 2 flows for Pb+Pb at 40 AGeV H.Stoecker et al., JPG 31 (2005) S929 Small wiggle in v 1 at midrapidity is not described by HSD and UrQMD Too large elliptic flow v 2 at midrapidity from HSD and UrQMD for all centralities ! Experiment (NA49): breakdown of elliptic v 2 flow at midrapidity ! Signature for a first order phase transition ? New data from lowRHIC, flows L.Kumar for STAR Collaboration, QM2009: Central Au+Au s=9.2 GeV As to azimuthal anisotropy, the RHIC results are consistent with NA49 data 3 fluid hydro with hadronic EoS Y.Ivanov, V.Russkikh, arXiv: Softening of EoS is needed Collapse of the directed flow (?) Yu.Ivanov, E.Nikonov, W.Noerenberg, A.Shanenko, V.Toneev, Heavy Ion Physics 15 (2002) 117. Two-fluid hydro, EoS with crossover phase transition. H.Stoecker, arXiv: H.Stoecker, Nucl. Phys. A750 (2005) 121. One-fluid hydro, EoS with the first order phase transition. first not high statistics data (stars): NA49 collaboration, Phys. Rev. C68 (2003) a linear extrapolation of the AGS data indicates a collapse of the directed proton flow at E lab 30 AGeV Collective flow: v 2 excitation function Collective flow: v 2 excitation function Proton v 2 at low energy shows sensitivity to the nucleon potential. Cascade codes fail to describe the exp. data. NICA energies: transition from squeeze-out to in-plane elliptic flow out-of-plane NCQ scaling of elliptic flow v 2 Phys. Rev. Lett. 98, (2007) Mesons Baryons Quark-like degrees of freedom. Evident indication of strong coupling? flow per constituent At RHIC energies elliptic flow develops at partonic level. What about 40 AGeV ? Idea of flow per constituent Coalescence/Recombination At RHIC energies elliptic flow develops at partonic level. What about 40 AGeV ? v 2 / as a function of particle density NA49 Collaboration, Phys. Rev. C68 (2003) Viscosity-to-entropy ratio minimum bias Au+Au, s=200 GeV Lower bound of /s=1/4 in the strong coupling limit (P.Kovtun et al. PRL 94 (2005) ) L.P.Csernai et al. PRL 97 (2006) ; R.Lacey at al. PRL 98 (2007) /s for several substances Strong indication for a minimum in the vicinity of T c Partonic fluid Hydrodynamic scaling Location of the CEP (?) R.Lacey et al. arXiv: Results for an isobar at the critical pressure P c and one above/below it T- B correlates at the freeze-out. First esatimate T~( ) MeV, B ~( ) MeV /s is a potential signal of the CEP Flow excitation function A sign of chiral symmetry restoration M.Volkov et al., PL B424 (1998) 235 S.Chiki, T.Hatsuda, PR D58 (1998) Invariant mass distribution for Pion annihilation into 2 photons (preliminary) V.Toneev and V.Skokov, Round Table I,III, Dubna (2005,2008) Central Au+Au (40 AGeV) res. total 5 AGeV Maximum is noticeably washed out but the yield is not so small The volume of the box is 2.4 by 2.4 by 3.6 fm. The topological charge density of 4D gluon field configurations. The lattice-based animation by Derek Leinweber Topological transitions have never been observed directly (e.g. at the level of quarks in DIS). An observation of the spontaneous strong parity violation would be a clear proof for the existence of such physics. In QCD, chiral symmetry breaking is due non-trivial topological effect; among the best evidence of this physics would be event-by-event strong parity vilation. Non-zero angular momentum (or equivalently of magnetic field) in heavy ion collisions make it possible for P - and CP -odd domains to induce charge separation (up-down quark asymmetry) in the produced particles (D.Kharzeev, PL B633 (2006) 260). Measuring the charge separation with respect to reaction plane was proposed by S.Voloshin, Phys. Rev. C70 (2004) Preliminary STAR data: hep- ph/ Parity violation in strong interactions Parity violation: experiment See: S.Voloshin, QM2009 Observed signature has excellent statistical sagnificance for Au+Au and Cu+Cu at top RHIC energies, and follows the expecterd trends. Other effects, especially resonance decays, can also lead to a signal, but so far no background effect can explain observab le signal size and centrality dependence. Combination of intense B and deconfinement is needed for parity violation; disappearance of signal is a new signature of turn-off of deconfinement, s=11 GeV ? The quarkyonic phase transition L.McLerran, R.Pisarski, Nucl. Phys. A796 (2007) 83. Model of large N c TCTC Quark loops are always small by 1/N C T C does not depend upon baryon density! Forweakly coupled gas of quarks. Quarkyonic Matter: Confined gas of perturbative quarks! Nuclear physics is in a width of order 1/N 2 C around the baryon mass! N C =3 ? Large but finite N C Mesons: quark-antiquark, noninteracting (~N C -1/2 ), masses ~ Baryons: N quarks, masses ~, baryon interactions ~ Quarkyonic phase boundaries LatQCD: Fodor, Katz, Schmidt, JHEP 0703 (2007) F-hydrodynamics, central Au+Au: Yu.Ivanov, V.Toneev. A.Andronic et al., ; Braun-Munzinger, CBM Meeting, March 2009, Darmstadt, DOC-2009Mar-49-1 E=4 AGeV E=2 AGeV quarkyonic boundary ? Multibaryon correlations: Random Matrix Method R.Nazmitdinov et al., PR C79 (2009) [arXiv: ] L.McLerran, QM2009, Conjectured Phase Diagram for Nc = 3 NICA Physics in the NICA energy range is rich and attractive, however PT in HIC is not a stable state but transitional one evolving in finite space/time There is no single decisive (crucial) signal: Scanning of all signals in energy, system size and impact parameter Conclusions There is no model There is no model (simulation code) which takes into account dynamics of PT.. Further perspectives are related to PHSD model (Bratkovskaya, Cassing) and hybrid kinetic-hydro approach (Frankfurt, Dubna) heat compression NICA Thank you for attention ! Dileptons and -meson spectral function NA60 + - data at 158 AGeV High precision NA60 data allow to distinguish among in-medium models Clear evidence for a broadening of the -meson spectral function (chiral symmetry restoration?) NA60 Collaboration, PRL 96 (2006) (G.Brown, M.Rho) How it will look like at s 11 GeV ? ( B ) Remarks Brown-Rho scaling QCD sum rules J.Ruppert, T.Renk and B.Muller, Phys. Rev. C73 (2006) To be consistent with QCD sum rules, both the collision broadening and dropping -mass should be taken into account (relation to the quark condensate ?) Dileptons carry a direct information on the -meson spectral function only if the assumption on vector dominance is valid (G.E.Brown and M.Rho, nucl- th/ ; nucl-th/ ). This is not so in the Harada- Yamawaki vector manifestation of Hidden Local Symmetry HLS (M.Harada and K.Yamawaki, Phys. Rept. 381 (2003) 1). In this case the electromagnetic coupling is governed by the parameter a of HLS theory which runs with temperature and density (see G.E. Brown et al., arXiv: ).