Presentation on theme: "Dynamic Modeling for Relativistic Heavy Ion Collisions"— Presentation transcript:
1Dynamic Modeling for Relativistic Heavy Ion Collisions Huichao SongPeking UniversityCPOD2014, Bielefeld, Germany, Nov.17-Nov.21, 201411/20/2014
2QGP-the most perfect fluid in the world? BNL News, 2005How perfect is the QGP fluid?
3What is viscosity Assume: (RHIC&LHC) Shear viscosity – measures the resistance to flowact against the buildup of flow anisotropyBulk viscosity – measures the resistance to expansionact against the buildup ofradial flowHeat conductivity – measures the ability of heat transferAssume: (RHIC&LHC)
8Extracting QGP viscosity from elliptic flow data – VISHNU results
9VISHNU hybrid model & QGP viscosity H. Song,et.al, PRL2011MC-KLNMC-Glauber-Main uncertainties come from initial conditions-Other uncertainties (much smaller)-Initial flow, bulk viscosity, single shot vs. e-b-e calculations(each of them shift V2 by a few percent, partial cancellation among them)
10V2 at RHIC and LHCSong, Bass & Heinz, PRC 2011The average QGP viscosity is roughly the same at RHIC and LHC
11LHC: spectra for identified hadrons Song, Bass & Heinz,PRC 2014-a nice fit of spectra for pions, kaons and proton
12Spectra of Strange & Multi-strange Hadrons X.R. Zhu, H. Song et al., in preparation-a nice fit of spectra for Lambda, Xi, and Omega
13for pions, kaons & protons at LHC VISHNUSong, Bass & Heinz,PRC 2014A very nice fit of V2(PT) for all centrality bins at LHC from VISHNU hybrid model
14v2 of Strange & Multi-strange Hadrons X.R. Zhu, H. Song et al., in preparation-Nice descriptions of Lambda, Xi and Omega V2 at various centralities
15Initial State Fluctuations, Final State Correlations & the QGP viscosity
16Uncertainties from Initial Conditions H. Song, S. Bass, U. Heinz, T. Hirano, and C. Shen, PRL2011MC-KLNMC-GlauberMain uncertainties come from initial conditionsMC-KLN, larger HIGHER value of QGP viscosityMC-Glauber, smaller LOWER value of QGP viscosity
17MC-KLN & MC-Glauber initializations & V3 Pure viscous hydro simulations :Qiu, Shen & Heinz, PLB2012V3 prefer lower value of QGP viscosity
18Initialization & Pre-equilibrium: Updates after 2011 -fluctuations of nucleon positions:MC-Glauber, MC-KLN-fluctuations of color charges (in the framework of CGC):IP-Glasma: B. Schenke et al., arXiv: ; [nucl-th]Correlated Fluctuation: B. Muller & A. Schafer, arXiv: [hep-ph].-fluctuations of local gluon numbers (in the famework of MC-KLN):Multiplicity fluctuations: A. Dumitru and Y. Nara, Phys. Rev. C 85, (2012)-Pre-equilibriums:URQMD initialization: H.Petersen & M. Bleicher, Phys. Rev. C81, ,2010AMPT initialization: L. Pang, Q.Wang & X.Wang, arXiv: [nucl-th]EPOS/NEXUS initialization: K. Werner et al., Phys. Rev. C83:044915,2011… … … …Mostly, the effects of initializations /pre-equilibrium dynamics was studied with ideal hydro. Their quantitative influences on are still unknown.
19Flow at RHIC & LHC: results from IP-Glasma + MUSIC Gale, Jeon ,Schenke, Tribedy &Venugopalan PRL2013
20New Observables for Higher Order Flow Harmonics Luzum & Ollitrault,Qiu & Heinz,12-08C. Gale et al.12-09-They are all sensitive to the QGP viscositywill constrain initialization models, tightening the limit on-A further study of flow data in different aspects, using e-b-e hybrid model
22Massive data evaluation Early CHIMERA Results(Comprehensive Heavy Ion Model Evaluation and Reporting Algorithm)Spectraspectraelliptic flowHBTR. Soltz, et al., PRC2013Please also refer to the work from MSU-DUKE collaboration, arXiv:
23Massive data evaluation Bernhard & Bass, JET collaboration
24Bulk Viscosity Long , but not full lists of articles: J.Noronha-Hostler, J.Noronha and F.Grassi, arXiv: [nucl-th]M. Habich and P. Romatschke, arXiv: [hep-ph].J.Noronha-Hostler, et.al., Phys.Rev. C 88, (2013)K.Dusling and T.Schäfer, Phys.Rev.C 85, (2012)P. Bozek, Phys. Rev. C81, (2010)H.Song and U.WHeinz, Phys. Rev. C81, (2010)G.Torrieri et al. Phys.Rev. C78, (2008).K. Rajagopal et al. JHEP 1003, 018(2008) .A. Monnai et al. Phys.Rev. C (2009)R.Fries et al. Phys.Rev. C (2008) .… … … … … …
25The interplay between shear and bulk viscosity Visc. suppressionof elliptic flowshear visc.shear+ bulk visc.idealSong & Heinz PRC09QGPHRGMin. AdS/CFTprediction-Bulk viscous effects are much smaller than shear ones due to the critical slowing down near phase transition (Song & Heinz PRC09)-One can extract the QGP shear viscosity from exp data without large contamination from bulk viscosityIntroduction25
26Ultracentral Collisions: bulk visc. & NN correlations Shen, Qiu and Heinz 2013G. Denicol, QM2014-MC-Glauber & MC-KLN: can not simultaneously fit V2 and V3-IP+Glasma + NN correlations + bulk viscosity nicely reproduces Vn inultra-central collisions
27Soft Particle Yields, Chemical & thermal Freeze-out at the LHC J. Stachel,SQM 2013Tch = 165MeVTch = 150MeVv.s.
28dN/dy for identified hadrons (RHIC & LHC) Song, Bass & Heinz,PRC 2014RHIC : 200 A GeV Au+AuLHC : 2.76 A TeV Pb+Pb-VISHNU nicely describes the multiplicity for pions, kaons & protons-B-Bbar annihilations plays an important role for a nice fit of the proton dataVISHNU : Tsw= 165MeVPlease also refer to F. Becattini et al., PRC2012
29dN/dy for identified hadrons (LHC) X.R. Zhu, H. Song et al., in preparation-VISHNU nicely describes the multiplicity for various hadrons at the LHC
30dN/dy for identified hadrons (LHC) X.R. Zhu, H. Song et al., in preparationVISHNUmost central collisions
31Statistical Model vs. VISHNU Statistical Model : Tch ~ 150 MeVVISHNU : Tsw= 165MeV- Statistical Model: Tch is extracted from final hadron yields; averaged chemical freeze-out temperature for final stable hadrons- VISHNU: Tsw corresponds QGP chemical freeze-out; different hadrons may have different chemical freeze-out temperature.
32Chemical freeze-out for various hadrons in UrQMD X.R. Zhu, H. Song et al., in preparation
33Thermal freeze-out for various hadrons in UrQMD X.R. Zhu, H. Song et al., in preparation-earlier freeze-out for Xi and Omega!
35Elliptic flow for phi at the LHC Song, Bass & Heinz, PRC 2014200A GeVAu+Au-Hadron cascade: small cross sections for phi-mass ordering between phi and proton are independent of collision energies, centralities & theoretical detailsT. Hirano3+1-d ideal hydro+JAM
36Elliptic flow for phi at the LHC Song, Bass & Heinz, PRC 2014ALICE 2014
37Elliptic flow for phi at the LHC Song, Bass & Heinz, PRC 2014STAR PreliminaryALICE 2014
41Summary -Extraction from elliptic flow data using VISHNU indicates: (MC-Glauber; MC-KLN)-Slightly larger averaged QGP viscosity at the LHC-Recent developments on initialization models: color charge fluctuations;multiplicity fluctuations; initial flow fluctuations … …-To implement e-b-e simulations to further study other flow will help us to constrain initialization models, tightening the limit on-New flow data: triangular flow & higher order flow harmonics, higher-order event plane correlations e-b-e vn … ...-massive data evaluation are needed-VISHNU could nicely describe the yields of various hadrons-B-Bbar annihilations is important to describe the proton yields at the LHCVISHNU: an indication of different chemical freeze-out temperature for various hadrons