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Femtoscopy with Exotic Species

Santa Clara vineyard, Troja, Prague. Femtoscopy with Exotic Species. Petr Chaloupka and Michal Šumbera for the STAR collaboration Nuclear Physics Institute ASCR Ř e ž /Prague. WPCF 2007, Santa Rosa, Sonoma, California, August 1 st –3 rd , 2007.  +.  -. K +. K -. K 0 S. p.  p. .

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Femtoscopy with Exotic Species

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  1. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Santa Clara vineyard, Troja, Prague Femtoscopy with Exotic Species Petr Chaloupka and Michal Šumbera for the STAR collaboration Nuclear Physics Institute ASCR Řež/Prague WPCF 2007, Santa Rosa, Sonoma, California, August 1st–3rd, 2007

  2. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 + - K+ K- K0S p p             +        -  -   K+    K- Phys.Rev.Lett.91:262302,2003J.Phys.G30:S1059-S1064,2004 A. Kisiel, PhD thesis  - - K0S     p Phys.Rev.C74:054902, 2006    p P. Chaloupka, arXiv:0705.3480 J.Phys. G32, S537-S540, 2006 Nucl.Phys.A774:603-606,2006 AIP Conf.Proc.828:610-614,2006 Nucl.Phys.A749:283-286,2005   Phys.Rev.C71:044906, 2006 G. Renault, hep-ex/0406066 G. Renault, PhD thesis    prelim or final result available STAR femtoscopy matrix

  3. 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 Two-particle correlation function N.B. prime means in the pair CMS frame

  4. ¯ ¯ p(p) : scattering length • Correlation due to strong FSI only • Proton-lambda • source size measured • CF fitted usingknown potential • Antiproton-lambda • unknown interaction potential • same potential form as in p-lambda assumed • For antiproton-lambda scattering length extracted for the first time STAR, Phys.Rev.C71: 044906, 2006 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05

  5. STAR, Phys.Rev.C71: 044906, 2006 • The source radii extracted • from p − L and p − L • corrrelation function agree • withthe flow expectation. • The radii extracted from p −L • and p −L are significantly • smaller. This may be due to • imperfect treatment of purity • corrections?

  6. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Why correlations? • Why is  elliptic flow comparable to other hadrons? Is that all suggesting early partonic collectivity? •  (as well as other multi strange baryons) may have thermal freeze-out behaviour differing from the other hadrons: early decoupling? • What is the production mechanism of *(1530)resonance?

  7. 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 -production @RHIC: elliptic flow Au+Au √sNN=200 GeV Sevil Salur QM’05 Nucl.Phys.A774:657-660,2006

  8. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 0.13 -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) • ,K, p <T> at 200 GeV > 62 GeV Tfo at 200 GeV =62 GeV • <T> at 200 GeV = 62 GeV Tfo at 200 GeV > 62 GeV Sevil Salur @ QM’05 Nucl.Phys.A774:657-660,2006

  9. 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 U. Heinz, J. Phys. G31,S717, 2005 Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05

  10. Collision rate for meson-meson (MM), meson-baryon (MB) and baryon-baryon (BB) at central collisions. The (dark) grey zone stands for qgp (mixed) phase, which is determined by the center cell. Influence of the hadronic phase succeeding the QGP C. Nonaka, S. Bass: Phys.Rev.C75:014902,2007: Hydro+UrQMD Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05

  11. correlations in Au+Au • Coulomb and strong [ 0(1530) ] final state interaction effects present. • Centrality dependence observed, particularly strong in the 0(1530) region

  12. -systematics: the summary • No significant energy dependence • Strong system dependence Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05

  13. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 0(1530) From m to C(k*)‏ 0(1530)‏ STAR preliminary 200 GeV AuAu 40-80%

  14. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Life time [fm/c] : (1020) = 44   (1520) = 13 (1385) = 5 K(892) = 4     Resonant states in system

  15. Breit-Wigner Fit 2/ndf 336.8 / 268  1.531 +/- 0.001  0.015 +/- 0.002 STAR Preliminary Au+Au @ sNN = 200 GeV Rotational Background Subtraction Background well described Visible signal before subtraction STAR Preliminary Au+Au @ sNN = 200 GeV S / (S+B)  8.6 Mass agrees with PDG ~60% wider (detector resolution) R. Witt@QM’06 J.Phys.G34:S921-S924,2007

  16. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Transverse Momentum Spectra • Measurements in 7 pT bins • out to ~5 GeV/c • 3 centralities • Fit with mT-exponentials • Mid-rapidity yields • scale ~linearly with Npart • same as  STAR, PRL 98:062301,2007. Richard Witt @ QM’06 J. Phys.G34:S921-S924,2007

  17. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Thermal Model • Thermal model (THERMUS)‏ • ratios at chem • Resonance pattern • suppressed K*/K • level */ • suppressed */  • enhanced */ • suggests significant hadronic scattering R. Witt@QM’06 J.Phys.G34:S921-S924,2007 Richard Witt – for the STAR Collaboration

  18. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 A) faster particle flying away • Interaction time is shorter • 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 is longer • Stronger correlation S. Voloshin, R.Lednický, S. Panitkin, Nu Xu, Phys.Rev.Lett.79(1997)4766. Measuring production offset by kinematic selection • 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

  19. Simplified idea of CF asymmetry(valid for Coulomb FSI) Assume  emitted laterthan por closer to the center  x v Longer tint Stronger CF v1  CF  k*x > 0 v> vp p p v2 Shorter tint Weaker CF k*/= v1-v2 x v CF  v1 k*x < 0 v< vp p  v2 p R. Lednický @ QM’05 & WPCF’05

  20. STAR, PRL91: 262302, 2003 C+/C-method C A small sensitivity of the ratio to the emission asymmetry comes from the integration over several important contributions C+/C- Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05

  21. * 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

  22. 200GeV Au+Au: different centralities

  23. 200GeV Au+Au: central • Used model: S. Pratt's FSI • S. Pratt & S. Petriconi: P.R. C68, 054901(2003) • + • Emission points from hydro-inspired Blastwave • constrained byp-p HBT • A11≠ 0- shift in the average emission point betweenand  could be clearly seen showing that pion is catching up with the  in qualitative agreement with transversally expanding source. • Discrepancy inthe X* region: model over predicts both A00 and A11. AssumedX*source is too small?

  24. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Separation between particle 1 and 2 boosted to the pair rest frame sDr* r*out = T(rout – Tt )‏   r ( r t T rout [fm] -9 X- - <r*out> < 0 average emission point of X is positioned more to the outside of the whole fireballthan the average emission point of pion. X+ -1 STAR preliminary • sDr* sr(p) • homogeneity • regionof X-source is smaller then that of p Gaussian parametrization & Coulomb only <rout > = <rout(p) –rout(X)> Particle 2 source Particle 1 source rout [fm] (sDr*, rout) - two-parameter description of the source in the rest frame

  25. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 STAR preliminary STAR preliminary STAR preliminary STAR preliminary • Not like-sign • -unlike-sign • but baryon – • anti-baryon • ordering in • < rout>

  26. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 Summary on correlations • High statistics measurements of correlations were presented. • Coulomb and strong FSI were observed. • Very good sensitivity to source size in  peak was found. More theoretical is input needed. • Spherical harmonics representation of data allows to observe that pion is catching up with the  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!!

  27. Michal Šumbera, NPI ASCR, Prague, Czech Republic 1st ALICE Physics week, Erice 9/12/05 STAR The STAR Collaboration U.S. Labs: Argonne, Lawrence Berkeley, and Brookhaven National Labs U.S. Universities: UC Berkeley, UC Davis, UCLA, Caltech, Carnegie Mellon, Creighton, Indiana, Kent State, MIT, MSU, CCNY, Ohio State, Penn State, Purdue, Rice, Texas A&M, UT Austin, Washington, Wayne State, Valparaiso, Yale Brazil: Universidade de Sao Paolo China: IHEP - Beijing, IPP - Wuhan, USTC, Tsinghua, SINAP, IMP Lanzhou Croatia: Zagreb University Czech Republic: Nuclear Physics Institute England: University of Birmingham France: Institut de Recherches Subatomiques Strasbourg, SUBATECH - Nantes Germany: Max Planck Institute – Munich University of Frankfurt India: Bhubaneswar, Jammu, IIT-Mumbai, Panjab, Rajasthan, VECC Netherlands: NIKHEF/Utrecht Poland: Warsaw University of Technology Russia: MEPHI – Moscow, LPP/LHE JINR – Dubna, IHEP – Protvino South Korea: Pusan National University Switzerland: University of Bern

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