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The Effect of Dynamical Parton Recombination on Event-by-Event Observables. Marcus Bleicher & Stephane Haussler Institut für Theoretische Physik Goethe Universität Frankfurt Germany. Thanks. Katharina Schmidt Hannah Petersen Stephane Haussler Daniel Krieg Benjamin Lungwitz.
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The Effect of Dynamical Parton Recombination on Event-by-Event Observables Marcus Bleicher & Stephane Haussler Institut für Theoretische Physik Goethe Universität Frankfurt Germany Marcus Bleicher, ISMD Berkeley 08/2007
Thanks • Katharina Schmidt • Hannah Petersen • Stephane Haussler • Daniel Krieg • Benjamin Lungwitz • Elena Bratkovskaya • Manuel Reiter • Sascha Vogel • Xianglei Zhu • Horst Stoecker • Timo Spielmann Marcus Bleicher, ISMD Berkeley 08/2007
Outline of the talk • Introduction • The Quark-Molecular Dynamics • Charge fluctuations • Baryon-strangeness correlations • Charge transfer fluctuations (see backup) • Summary Marcus Bleicher, ISMD Berkeley 08/2007
Motivation At RHIC: look for signals of freely moving partons.(D, CBS,k)At FAIR/SPS:look for the mixed phase and the onset of deconfinement(w, k/p, p/p) E. Bratkovskaya, M.B. et al., PRC 2005 Marcus Bleicher, ISMD Berkeley 08/2007
Fluctuations are THE tool!? • Fluctuations might provide information on - deconfinement/confinement- correlation length- thermalization- nature of the QGP- critical point • Is it that easy?- finite time and volume- non-equilibrium- hadronization Marcus Bleicher, ISMD Berkeley 08/2007
Scaled variances • Non-trivial structures Detailed non-equilibrium studies necessary 4pi forward Lungwitz, Bleicher, in preparation Marcus Bleicher, ISMD Berkeley 08/2007
The tool: qMD • qMD : Quark Molecular Dynamics (a toy model for hadronization) • out-of-equilibrium transport model, (Vlasov equation) • provides a hadronization prescription • essentially realizes a dynamical quark recombination approach Marcus Bleicher, ISMD Berkeley 08/2007
Quark Molecular Dynamics Marcus Bleicher, ISMD Berkeley 08/2007
Trajectories Marcus Bleicher, ISMD Berkeley 08/2007
Hadronization procedure Marcus Bleicher, ISMD Berkeley 08/2007
Some properties: equilibrium Marcus Bleicher, ISMD Berkeley 08/2007
For ‘real’ physics use UrQMD initial state • dissolve strings into ‘free’ quarks • evolve system with qMD Marcus Bleicher, ISMD Berkeley 08/2007
Entropy consideration <N> <m> Marcus Bleicher, ISMD Berkeley 08/2007
Entropy and recombination Marcus Bleicher, ISMD Berkeley 08/2007
The idea behind conserved charge fluctuations Marcus Bleicher, ISMD Berkeley 08/2007
Fluctuations and suceptibilities Marcus Bleicher, ISMD Berkeley 08/2007
Comparison to lQCD (I) Marcus Bleicher, ISMD Berkeley 08/2007
Comparison to lQCD (II) Marcus Bleicher, ISMD Berkeley 08/2007
Hadron gas seems to be pretty similar to QGP… ( A. Majumder et al, Phys. Rev.C 74 (2006) 054901 ) Marcus Bleicher, ISMD Berkeley 08/2007
Charge ratio fluctuations Marcus Bleicher, ISMD Berkeley 08/2007
Pion gas, D ~ 4 Quark gas, D ~ 1 Marcus Bleicher, ISMD Berkeley 08/2007
Can one observe the fluctuations in the initial state? See e.g. Shuryak et al, Phys.Rev.C63:064903,2001 Marcus Bleicher, ISMD Berkeley 08/2007
Experimental results Marcus Bleicher, ISMD Berkeley 08/2007
Recombination and fluctuation Au+Au@200 AGeV parton fraction Dy=1 Marcus Bleicher, ISMD Berkeley 08/2007
See also… • Bialas: Recombination blur ratio fluctuations (Phys.Lett.B532:249-251,2002) • Nonaka: Recombination blurs ratio fluctuations (Phys.Rev.C71:051901,2005 ) • Ma: Hadronization blurs ratio fluctuations(SQM 2007) • Present work: Marcus Bleicher, ISMD Berkeley 08/2007
Baryon-Strangeness Correlations Marcus Bleicher, ISMD Berkeley 08/2007
Time evolution Au+Au@200 AGeV Dy=1 Marcus Bleicher, ISMD Berkeley 08/2007
Conclusions Marcus Bleicher, ISMD Berkeley 08/2007
Additional slides Marcus Bleicher, ISMD Berkeley 08/2007
Charge transfer fluctuations Marcus Bleicher, ISMD Berkeley 08/2007
qMD results on kappa Au+Au@200 AGeV Marcus Bleicher, ISMD Berkeley 08/2007