1 / 62

Workshop of European Group on Ultrarelativistic Heavy Ion Physics

Workshop of European Group on Ultrarelativistic Heavy Ion Physics. Close velocity Correlations. q. from STAR to ALICE. JINR, Dubna 9-14. 03. 2006. Jan Pluta, Warsaw University of Technology. The starting point. 1972 - 4 Kopylov and Podgoretsky settled the basics

duncan
Download Presentation

Workshop of European Group on Ultrarelativistic Heavy Ion Physics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Workshop of European Group on Ultrarelativistic Heavy Ion Physics Close velocity Correlations q from STAR to ALICE JINR, Dubna 9-14. 03. 2006 Jan Pluta, Warsaw University of Technology

  2. The starting point

  3. 1972 - 4 • Kopylov and Podgoretsky • settled the basics • of correlation femtoscopy: • correlation function, • mixing technique, • role of space-time charakterist... Podgorecki, Kopylov, Smorodinski Dubna, 1974 1975 ... Grishin, propane bubble chamber group and others in Dubna - measured the two-particle correlations 1981 Lednicky and Lyuboshitz solved the problem of final state interaction Weekly meeting of propane bubble chamber group.

  4. The basic notions Rlong p1 x1 p2 qside Rside x2 qout qlong Rout • HBT: Quantum interference between identical particles 2 C (q) Gaussian model (3-d): 1 • Final-state effects (Coulomb, strong) also can cause correlations, need to be accounted for q (GeV/c) Two-particle interferometry: p-space separation  space-time separation

  5. HBT at RHIC...

  6. HBT Excitation Function

  7. “RHIC HBT puzzle” STAR 130 GeV PHENIX 130 GeV • unexpected (small) sizes • Rout/Rside = (approx.)1 • Pt dependence do not agree with models • The same Pt dependence for pp, dAu and AuAu

  8. Z.Chajęcki, QM’2005 STAR DATA (pp,dAu,CuCu,AuAu@62GeV - prelim.) RHIC/AGS/SPS Systematics <kT>≈ 400 MeV (RHIC)<kT>≈ 390 MeV (SPS) Lisa, Pratt, Soltz, Wiedemann, nucl-ex/0505014 Pion HBT radii from different systems and at different energies scale with (dNch/dη)1/3

  9. System expansion: Initial vs Final Size Collisions at 200GeV only Smooth expansion of the system from p+p to Au+Au AuAu: system expands pp (dAu): no or less expansion Proton initial size = 0.89 fm from e-scattering

  10. 0.2 0.3 0.4 0.5 0.2 0.3 0.4 0.5 0.6 Transverse mass dependence in Au+Au STAR, Au+Au@200GeV, PRC71 (2005) 044906 0. 0. 0. .2 Calc. with Blast-Wave -Retiere, Lisa,PRC 70 (2004) 044907 In Au+Au pT (mT) dependence attributed to collective expansion of the source

  11. Consistency check on flow – kaons

  12. Hania Gos, Kromeriz’05

  13. More confirmation STAR preliminary

  14. Surprising („puzzling”) scaling Ratio of (AuAu, CuCu, dAu) HBT radii by pp • All pT(mT) dependences of HBT radii observed bySTAR scale with pp although it’s expected that different origins drivethese dependences HBT radii scale with pp Scary coincidence or something deeper? pp, dAu, CuCu - STAR preliminary

  15. Hania Gos, Kromeriz’05

  16. Catching up • Effective interaction time larger • Stronger correlation C- Moving away • Effective Interaction time smaller • Weaker correlation C+ “Double” ratio • Sensitive to the space-time asymmetry in the emission process C+ C- 1 R.Lednicky, V. L.Lyuboshitz, B.Erazmus, D.Nouais, Phys.Lett. B373 (1996) 30. k* Adam Kisiel, Fabrice Retiere Nonidentical particle correlations – the asymmetry analysis Heavier particle faster Lighter particle faster Kinematics selection along some direction e.g. kOut, kSide, cos(v,k)

  17. Pion-Kaon at 200 AGeV kaon faster pion faster STAR preliminary • Good agreement for same-charge combinations • Clear emission asymmetry signal Out double ratio Side double ratio + 0.9 syst. Sigma: 17.3± 0.8fm - 1.6 syst. + 6.1 syst. Mean: -7.0±1.2 fm - 4.0 syst.

  18. Pion-Proton 130 AGeV proton faster pion faster • Good agreement for identical and opposite charge combinations • We observe Lambda peaks at k*~decay momentum of Λ Λ peaks STAR preliminary Side double ratio Sigma: 15.1± 0.4 fm + 1.0 syst. - 1.5 syst. Mean: -7.4± 0.9 fm + 1.9 syst. - 3.4 syst. Out double ratio Fit assumes source is a gaussian in r*out

  19. Hania Gos, Kromeriz’05

  20. Adam Kisiel, Kromeriz’05 Origins of asymmetry pion emission times • Measures asymmetry in pair rest frame is a combination of time and space shifts in source frame • In heavy-ion collisions one expects difference in emission time from resonance decays all primordial pion average = 16.1 kaon average = 14.8 time shift = 1.3 kaon emission times all THERMINATOR calculation primordial

  21. pion emission points Space asymmetry from flow side • Transverse momentum of particles is composed of the thermal (randomly distributed) and flow (directed “outwards”) components • With no flow average emission point is at center of the source and the length of homogeneity is the whole source • Flow makes the source smaller (“size”-p correlation) AND shifted in outwards direction (x-p correlation) • For particles with large mass thermal motion matters less – they are shifted more in “out” direction. The difference is measured as emission asymmetry. out kaon emission points proton emission points THERMINATOR calculation

  22. Ry Rx Time Fourier coefficients of HBT() oscillations initial = final • Out-of-plane sources at freeze-out • Pressure and/or expansion time was not sufficient to quench initial shape • From v2 we know... • Strong in-plane flow → significant pressure build-up in system eccentricity  Short expansion time plays dominant role in out-of-plane freeze-out source shapes STAR Collaboration, nucl-ex/0312009

  23. Dmitri PeresounkoDirect photon interferometry PHENIX; d+Au collisions at √sNN=200 GeV

  24. Paul Chung, Stony Brook ImagingTechnique Emitting source Technique Devised by: D. Brown, P. Danielewicz, PLB 398:252 (1997).PRC 57:2474 (1998). Inversion of Linear integral equation to obtain source function 1D Koonin Pratt Eqn. Encodes FSI Source function (Distribution of pair separations) Correlation function Inversion of this integral equation == Source Function

  25. T.Csorgo, Kromeriz’05 Rewiew of Bose-Einstein/HBT Correlations in high energy heavy ion physics Model F Model G Question 0: Do the models (E,F,G,H) describe the data? Answer 0: These models fail, but this is not a puzzle. Q. 1: Are any other models that descibe the data? A. 1: Yes, there are three models (A,B,C) that cannot be excluded (Conf. Lev. > 0.1 %) Q. 2: Do these models have anything in common? A. 2: Yes, and this where the data (D) are. This common part is what Nature is trying to tell us. Model A D Model B Model C Model H Model E Nature hides her secrets in data (D)

  26. Acceptable Comparison of results of models

  27. Comparison of results of models

  28. Comparison of results of models

  29. Comparison of results of models

  30. Comparison of results of models

  31. Comparison of results of models

  32. Comparison of results of models

  33. Comparison of results of models

  34. Comparison of results of models

  35. Acceptable Comparison of results of models

  36. Comparison of results of models

  37. ~Acceptable Comparison of results of models

  38. ~Acceptable Comparison of results of models

  39. Comparison of results of models

  40. T.Csorgo, Kromeriz’05 The HBT test Less unpromising models: don’t fail fitting Au+Au HBT data @ RHIC • nucl-th/0204054 Multiphase Transport model (AMPT) Z. Lin, C. M. Ko, S. Pal • nucl-th/0205053 Hadron rescattering model `` T. Humanic • nucl-th/0207016 Buda-Lund hydro (hep-ph/9503494, 9509040) T. Csorgo, B. Lörstad, A. Ster et al. (nucl-th/0403074, /0402037, /0311102 ) • hep-ph/0209054 Cracow model (single freeze-out, thermal) W. Broniowski, A. Baran, W. Florkowski • nucl-ex/0307026 Blast wave model (Schnedermann, Heinz) M. A. Lisa, F. Retiere, PRC70, 044907 (2004) • hep-ph/0404140 Time dependent Duke hydromodel T. Renk • nucl-th/0411031 Seattle model (quantum opacity) J. G. Cramer, G. A. Miller, J.M.S. Wu, J.-H. Yoon • nucl-th/0507057 Kiev-Nantes model Borysova, Sinyukov, Akkelin, Erazmus, Karpenko -> More restrictive tests are needed: spectra, v2, HBT, dn/dy

  41. Spectra HBT F. Retiere, nucl-ex/0405024; F. Retiere and M. A. Lisa, nucl-th/0312024 Successfull models at RHIC (1): Blastwave T=106 ± 1 MeV <InPlane> = 0.571 ± 0.004 c <OutOfPlane> = 0.540 ± 0.004 c RInPlane = 11.1 ± 0.2 fm ROutOfPlane = 12.1 ± 0.2 fm Life time () = 8.4 ± 0.2 fm/c Emission duration = 1.9 ± 0.2 fm/c 2/dof = 120 / 86 (Errors are statistical only, CL = 0.91 %) Neglect of resonances v2

  42. Model features: Thermal model included (abundances driven by Tchem and B) Assumes full Hubble flow Sudden freeze-out (at a constant proper-time) Single freeze-out, Tchem = Tkin Boost-invariance nucl-th/0212053 Successfull model (2): Cracow model All resonances included, they decay but do not rescatter.

  43. Future plans at LHC

  44. RHIC/AGS/SPS Systematics ...and expectations for LHC <kT>≈ 400 MeV (RHIC)<kT>≈ 390 MeV (SPS) Assuming the same tendency: 40961/3=16 80001/3=20 Rexpected < 10fm

  45. Tom Humanic, Kromeriz’05 Pion freezeout time and z-position for LHC form rescattering calculations Pion freezeout times are about twice as long at LHC compared to RHIC

  46. Two-pion correlation function for LHC form rescattering calculations Projected 3D two-pion C2 for LHC Pb+Pb from rescattering for b=8 fm centrality and pT bin 0-200 MeV/c

  47. Transverse radius parameters for LHC vs. RHIC Transverse radius parameters are somewhat larger and show a stronger pT dependence for LHC compared with RHIC

  48. RLong and l parameters for LHC vs. RHIC RLong for LHC is almost twice as large as for RHIC reflecting longer freezeout times; l behaves about the same at LHC and RHIC

  49. Current status of momentum correlation analysis Results of PPR preparation; Chapter 6.3 Momentum Correlations • „HBT-analyser” – a dedicated sofrware for momentum coorelation analysis at ALICE - ready and integrated in Ali-root environment • Experimental factors specific for correlation analysis: track splitting, merging, two-particle resolution and PD - evaluated for different two-particle systems • Universal fitting procedure for identical and nonidentical particles „Corfit” – ready, but not integrated yet in Ali-root environment • Influence of hard processes (jets) on particle correlatins – under investigations • Single event pion interferometry will be possible at ALICE

More Related