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Selected results on s trong - and c oulomb-induced correlations from STAR experiment. Michal Šumbera Nuclear Physics Institute ASCR Řež /Prague. WPCF 2006, S ã o Paulo, 9 th –11 th Sept ember, 200 6. Space-time structure of multi-strange baryon source via - correlations
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Selected results on strong- and coulomb-induced correlations from STAR experiment Michal Šumbera Nuclear Physics Institute ASCR Řež/Prague WPCF 2006, São Paulo, 9th–11th September, 2006 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Space-time structure of multi-strange baryon source via - correlations (Petr Chaloupka) Motivation Update on previous analysis Comparison with predictions from UrQMD(?) Identical pion correlations (Michal Bysterský) Motivation/summary of previous analysis 1D imaging analysis of Au+Au and Cu+Cu STAR data on identical pions Outline Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Phys.Rev.Lett.91:262302,2003J.Phys.G30:S1059-S1064,2004 A. Kisiel, PhD thesis STAR, nucl-ex/0511003 G. Renault, hep-ex/0406066 G. Renault, PhD thesis RHIC femtoscopy matrix: Mike’s table (M. Lisa, ISMD, Kroměříž 2005) P. Chaloupka, J.Phys. Gxx ,2006, in print Nucl.Phys.A774:603-606,2006AIP Conf.Proc.828:610-614,2006 Nucl.Phys.A749:283-286,2005 prelim or final result available Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Why p-X correlations? • Why is Xelliptic flow comparable to other hadrons? Is that all suggesting early partonic collectivity? • X(as well as other multi strange baryons) mayhave thermal freeze-out behaviour differing from the other hadrons: e.g. early decoupling? • What is the production mechanism of X (1530)resonance? Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au √sNN=200 GeV Phys. Rev. Lett. 92 (2004) 052302 1 0 2 STAR Preliminary pT/n (GeV/c) Au+Au √sNN=62 GeV X-production@RHIC: elliptic flow Au+Au √sNN=200 GeV Sevil Salur QM’05 Nucl.Phys.A774:657-660,2006 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
0.13 X-production@RHIC: radial flow Most Central Collisions • Temperature Tfo is higher for baryons with higher strange quark content for Blast-wave fits. • Spectral shapes are different. Temperature Tfo (GeV) • p,K, p <T> at 200 GeV > 62 GeV Tfo at 200 GeV =62 GeV • X, W <T> at 200 GeV = 62 GeV Tfo at 200 GeV >62 GeV Sevil Salur @ QM’05 Nucl.Phys.A774:657-660,2006 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
What the hydro tells us about multistrange baryons at RHIC Heavy hadrons, which are particularly sensitive to radial flow effects, require the additional collective “push” created by resonant (quasi)elastic interactions* during the fairly long-lived hadronic rescattering stage between TcrandTd *) e.g. + * + U. Heinz, J. Phys. G31,S717, 2005 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Collision rate for meson-meson (MM), meson-baryon(MB) and baryon-baryon (BB) at central collisions. The(dark) grey zone standsfor qgp (mixed) phase, which is determinedby the center cell. Influence of the hadronic phase succeeding the QGP C. Nonaka, S. Bass: nucl-th/0607018: Hydro+UrQMD Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Resonant states in p-X system Life time [fm/c] : (1020) = 47 L(1520) = 13 S(1385) = 5 K(892) = 4 (1530) = 22 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Recent development (since WPCF05) • Re-run ofHBT analyses in order to extract in low kTbins: 125 MeV/c pT 1GeV/c) • Increased acceptance for pions from 0.5 to 0.8 • 2D-binning: 10cm wide vertex bins multiplicity bins replaced by 3D-binning: 10cm wide vertex bins multiplicity bins 5 event plane bins Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
(Re)analyzed data 200GeV AuAu, run IV data 41.4M events out of which 26.4M are from central trigger sample Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
dE/dx electron cut & - purity 2 cut around electron band dE/dx [eV/cm] dE/dx [eV/cm] Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Conclusion 1: dE/dx electron cut influnces but not the emission radii Rout, Rside or Rlong Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au @ 200GeV, centrality: 0-5% STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au @ 200GeV, centrality: 0-5% STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au @ 200GeV, centrality: 0-5% STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au @ 200GeV, centrality: 0-5% STAR preliminary Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Conclusion 2: Using two different pion purities we get to the same final C(k*) the systematic error from pion purity is under control Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
* From m to C(k*) *(1530) STAR preliminary 200 GeV AuAu 40-80% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Reaction plane binning improvement 62 GeV AuAu Without reaction plane binning With reaction plane binning Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
p-X correlations in Au+Au • Coulomb and strong ( X*1530 ) final state interaction effects present. • Centrality dependence observed, particularly strong in the X* region
p-Xsystematics: the summary • Strong • system dependence • No significant energy dependence Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Petr ChaloupkaWPCF05 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
If space-time ordering, select between two configurations: A) Both particles are moving away from each other B) One particle is catching up Final state interactions yield different correlations for these two configurations A) faster particle flying away • Interaction time isshorter • Weaker correlation B) faster particle catching up R.Lednický, V. Lyuboshitz, Sov.J. Nucl.Phys. 20(1982)770. R.Lednický, V. Lyuboshitz, B. Erazmus, D. Nouais, Phys.Lett. B 373(1996)30. • Interaction time islonger • Stronger correlation S. Voloshin, R.Lednický, S. Panitkin, Nu Xu, Phys.Rev.Lett.79(1997)4766. Measuring production offset by kinematic selection Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Spherical harmonics decomposition of non-identical particle correlations Z. Chajecki , T.D. Gutierrez , M.A. Lisa and M. López-Noriega,nucl-ex/0505009 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Spherical harmonics decomposition of non-identical particle correlations • DifferentAlmcorrespond to different symmetries of the source • A00- monopole size • A11- dipole shift in out-direction • A2m– quadrupole shape • ..... Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Petr ChaloupkaWPCF05 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
200GeV Au+Au central • A11≠ 0 - shift in the average emission point betweenp and X could be clearly seen showing that pion is catching up with the X in qualitative agreement with transversally expanding source.
Summary on p-Xcorrelations • High statistics measurements of p-Xcorrelations were presented. • Coulomb and strong FSI were observed. • Very good sensitivity to source size in X* peak was found. More theoretical is input needed. • Spherical harmonics representation of data allows to observe that pion is catching up with the X in qualitative agreement with transversally expanding source. • Prospect for the same type measurement after STAR detector upgrades and also with ALICE at LHC seems good!! Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
2. Identical pion correlations Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Fabrice Retière WPCF05 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Fabrice Retière WPCF05 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Michal Bysterský WPCF05 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Distribution of relative positions of particles with identical velocities and total momentum P Two particle wave funcion (QS+FSI) : Space-time emission function of particle i Imaging: a short introduction N.B. prime means in the pair CMS frame Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Inverting expression for angle averaged correlation function • Task of imaging is to determine the source S(r ) from C(q) by inverting the Koonin-Pratt integral equation: D. A. Brown and P. Danielewicz, Phys. Let B398(1997)252 Phys. Rev C, 57 (1998)2474 Code for inverting the angle averaged correlation function can be downloaded from http://www-phys.llnl.gov/Research/source_imaging/HBTprogs.html Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
S.S. Adler et al., (Phenix coll.): ArXiv:nucl-ex/0605032 “… The source parameters extractedfrom these functions at low kT, give first indications of a long tail for the pion emission source. Thesource extension cannot be explained solely by simple kinematic considerations. The possible roleof a halo of secondary pions from resonance emissions is explored.” Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Testing the reproducibility 1/2 10-40% 40-80% 0-10% RQMD, assuming isotropic Gaussian source, R=5fm, =0 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Testing the reproducibility 2/2 • Reproduction of the input parameters is not very good: RG/RG 5%, / 25%(!) (may be due to finite statistics, fit parameters effect, code itself?) • The shape of the distribution is reproduced rather well Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
The same data cuts as in the previus pion purity analysis were used except for the dE/dx electron cut N.B. All experimental data processed with single set of input parameters: Ndata=28,Nmodel=12,Neqcon=5 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
STAR: Au+Au, 40-80%, 250 < kT< 300 MeV STAR: Au+Au, 0-10%, 450 < kT< 600 MeV STAR preliminary Phenix: nucl-ex/0605032 PHENIX:Au+Au, 0-20%, 480 < kT< 600 MeV PHENIX: Au+Au, 40-90%, 200 < kT< 360 MeV Comparing STAR data to PHENIX Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Two simple source parametrizations N.B. Have not tried spheroid fit, yet Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 3 centrality bins 10-40% 40-80% 0-10% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 3 centrality bins 10-40% 40-80% 0-10% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 0-5% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 0-5% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 0-5% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05
Au+Au: 0-5% Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05