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φ and ω resonance decay modes Georgy Sharkov ITEP

φ and ω resonance decay modes Georgy Sharkov ITEP. , ω resonances. If resonance decays before kinetic freeze-out  Possible rescattering of hadronic daughters  Reconstruction probability decrease for hadronic mode. A.V. Stavinsky, Acta Phys. Polon B40; 1179-1184, 2009.

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φ and ω resonance decay modes Georgy Sharkov ITEP

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  1. φand ω resonance decay modes Georgy Sharkov ITEP

  2. ,ω resonances Ifresonance decays before kinetic freeze-out  Possible rescattering of hadronic daughters  Reconstruction probability decrease for hadronic mode A.V. Stavinsky, Acta Phys. Polon B40; 1179-1184, 2009 ω(782) π+ π-π0B.R. 0.89 (c = 23 fm) ω(782) π+ π-B.R. 0.017 ω(782) π0B.R. 0.089 ω(782) e+e-B.R. 0.000072 φ(1020) K+ K-B.R. 0.49 (c = 44 fm) φ(1020)  ηB.R. 0.013 φ(1020) e+e-B.R. 0.000297 χc0 (c = 37 fm)

  3. t hadrons with &without QGP quarks&gluons

  4. Model l0~cτβ/√(1-β2) ~ ~(β=1/3 for this estimate)~ ~15fm(for φ) & 8fm(for ω) li l0 η η φ  li~2fm for any hadron & 1fm for any pair of hadrons l hadronization Kinetic freeze-out G. Sharkov ITEP FRRC

  5. Model • Upper line – lepton mode Splitting – two hadron and hadron-photon modes l -decay products trajectory length within matter φ β= 1/3 ω l,fm G. Sharkov ITEP FRRC

  6. Is it really possible measurement? • Existing data from PHENIX&STAR • B • B • B • B φ/w  e+e- φ K+K- w p+p-p0, p0g φηg ? G. Sharkov ITEP FRRC

  7. Φ(1020) K+ K-B.R. 0.49 c = 44 fm Φ(1020) e+e-B.R. 0.000296 c = 44 fm d+Au PHENIX Φ K+K- STAR Preliminary √sNN = 200 GeV Au+Au PHENIX Φ e+e- √sNN = 200 GeV

  8. ω(782) π+ π-π0B.R. 0.89 c = 23 fm ω(782) π0 B.R. 0.089 c = 23 fm η(547) π+ π-π0B.R. 0.23 c = 167225 fm PHENIX η,ω π+π-π0 p+p Au+Au p+p ω π0 PHENIX √sNN = 200 GeV ω π0 PHENIX G. Sharkov ITEP FRRC

  9. Y. Nakamiya Hiroshima University, Japan for the PHENIX collaboration QM 2008, India • Branching ratio between e+e- and K+K- may be sensitive to mass modification, since Mphi is approximately 2  MK. • -> Compare yields of fe+e- and f K+K- G. Sharkov ITEP FRRC

  10. Φ Production  K+K- and e+e- e+e- K+K- • The leptonic channel yield is a little higher than hadronic channel • More accurate measurement is required to confirm whether there is branch ratio modification G. Sharkov ITEP FRRC

  11. To Do • To make calculationsfor the effect of interest within realistic model • To create algorithm for photonic modes identification in AA interactions • To check this algorithm for CBM conditions with realistic simulations G. Sharkov ITEP FRRC

  12. Model requirements • realistic representation of particles (γ!) • evolution in time • distinguish particles produced in dense and rare phases EPOS • Energy conserving quantum mechanical multiple scattering approach,based on • Partons (parton ladders) • Off-shell remnants, and • Splitting of parton ladders. G. Sharkov ITEP FRRC

  13. (elastic scattering) + Statistical Hadronization Models P. Braun-Munzinger, I. Heppe, J. Stachel, Phys. Lett B465 (1999) 15; F. Becattini, J. Manninen , M. Gazdzicki, Phys.Rev. C73 (2006) 044905, hep-ph/0511092; J. Cleymans, H. Oeschler, K. Redlich, S. Wheaton, Phys.Rev. C73 (2006) 034905, hep-ph/0511094; J. Rafelski, M. Danos, Phys. Lett. 97B (1980) 279; J. Rafelski, J. Letessier, J. Phys. G: Nucl. Part. Phys. 28 (2002) 1819 and blast-wave fits E. Schnedermann, J. Sollfrank, U. Heinz, Phys. Rev. C48(1993) 2462 [8] F. Retiere, J.Phys. G30 (2004) S827-S834,nucl-ex/0405024; J. Adams, STAR Collaboration,Phys. Rev. Lett. 92 (2004) 112301; I. Kraus, NA49Collaboration, J.Phys. G31 (2005) S147-S154 G. Sharkov ITEP FRRC

  14. EPOS √s=200GeV dAu K. Werner Nucl. Phys. B175 (2008) 81 Pb+Pb @ 17.3 GeV(SPS) Au+Au @ 200GeV (RHIC) KlausWERNER, Phys. Rev. Lett. 98, 152301 (2007), arXiv:0704.1270. G. Sharkov ITEP FRRC

  15. EPOS & UrQMD π+ G. Sharkov ITEP FRRC

  16. Generate EPOS statistics • Check all decay modes • Tune EPOS output for CBMROOT • Produce CBMROOT events with full ECAL G. Sharkov ITEP FRRC

  17. G. Sharkov ITEP FRRC

  18. G. Sharkov ITEP FRRC

  19. UrQMD EPOS G. Sharkov ITEP FRRC

  20. G. Sharkov ITEP FRRC

  21. G. Sharkov ITEP FRRC

  22. Extra slides G. Sharkov ITEP FRRC

  23. Direct photons analysis Re: [URQMD] ftn15 (fwd) a1(1260) η' ω K* "hm, yes photons are mesons in urqmd. however, photons should not be calculated within the urqmd, but explicitely outside with a different code. everybody should ignore all processes with photons involved. we will move them out of the model in the next version. cheers, Marcus Bleicher" f1(1285) • Only from decay • 2 γγelastic scatterings(?!) UrQMD code UrQMD generator & cumulativeprocesses CBM simulation meeting

  24. Formulas G. Sharkov ITEP FRRC Stavinskiy,ITEP,10.06.08

  25. e+ e- f,w Momentum Electron ID gEnergy g p0 g p0 g g K+ p+ w f K- p- g Hadron ID Momentum Momentum Hadron ID Electron, hadron and photon in PHENIX f/w  e+e- • PHENIX acceptance • -0.35 < η < 0.35 • 2 x 90°in azimuthal angle for two arms • Event selection • BBC • Electron ID • RICH • EMCal • photon ID • EMCal • Hadron ID • TOF • EMCal-TOF w p+p-p0, p0g f  K+K- G. Sharkov ITEP FRRC

  26. Extended f  K+K- analysis Consistency between f  K+K- and f e+e- f Double ID analysis K+ K- f candidates d+Au no ID analysis 0-20% h+ h- f candidates No ID Single ID Double ID No ID Single ID Double ID e+e- Single ID analysis M.B. p+p K+ or K- h+ or h- f candidates f d+Au 0-20% M.B. p+p • fK+K- measurements have been extended to both higher and lower pT using new methods, i.e. no kaon ID and single kaon ID methods. • The three independent kaon analyses are consistent with each other. In p+p, spectra of e+e- and K+K- show reasonable agreement! G. Sharkov ITEP FRRC

  27. Spectra comparison between fe+e- and f K+K- f e+e- AuAu MB f e+e-20-40% x 10-3 fe+e- 40-92% x 10-1 f K+K- AuAu MB (no PID) f K+K- AuAu MB (double PID) fK+K- AuAu MB (PRC72 014903) f K+K- 20-40% x 10-3 (double PID) f K+K- 40-92% x 10-1 (double PID) fK+K-40-92% x 10-1 (PRC72 014903) Au+Au M.B. 40-92% 20-40% Errors are too large to make any clear statement about the comparison of spectra for f  e+e- and f  K+K-. G. Sharkov ITEP FRRC

  28. Yield comparison between fe+e- and f K+K- Question 1’: Have we observed changes of yield between e+e- and K+K- ? • Comparison of integrated yield is not enough, because • mass modification effects depend on the pT region. • Low pT mesons tend to decay inside the hot/dense matter f f Low pT High pT • In addition, • To determine the integrated yield, an extrapolation to lower pT is needed. • There is a large uncertainty in the calculation. • Thus, pT-dependent information is essential for comparison. Now, we should ask Have we observed changes of spectra between e+e- and K+K- ? G. Sharkov ITEP FRRC

  29. What is the difference? • Modes absorbtion vs Mass modification • Standard mesons vs modified mesons • φ→KK & φ→η • Modes absorbtion vs K/K* ratio • Lepton modes vs thermal model • Hadron stage vs equilibrium stage • Modes absorbtion vs both other approaches • Internal cross-check - 3 modes G. Sharkov ITEP FRRC Stavinskiy,ITEP,10.06.08

  30. Real σMN in matter can differ from that in free space • ω photoproducton on nuclear targets (ELSA) M.Kotulla et al., ArXiv: nucl-ex/08020980 σωN ≈ 70 mb (in nuclear medium, 0.5 < P <1.6 GeV/c) σωN ≈ 25 mb (in free space - the model calculations) •  photoproducton on nuclear targets T.Ishikawa et al., Phys.Lett.B608,215,(2005) σφN= 35 ± 14 mb (in nuclear medium) σφN ≈ 10 mb (in free space) “φ-puzzle” photoproducton on nuclear targets G. Sharkov ITEP FRRC

  31. wp0g dAu MB (PRC75 151902) wp0p+p- dAu MB(PRC75 151902) w e+e- pp MB (PHENIX preliminary) wp0g pp MB (PRC75 151902) wp0p+p- pp MB(PRC75 151902) wp0g pp ERT (PHENIX preliminary) wp0p+p- pp ERT (PHENIX preliminary) Measurements of win wide pT range pT spectra of w are measured for several decay modes in d+Au and p+p. w d+Au p+p G. Sharkov ITEP FRRC Spectra show good agreement among several decay channels.

  32. Branching ratiosas an instrument for density integral measurements • mesons ( mesons) • new source of information • Interplay between different ALICE subdetectors(?) Stavinskiy,ITEP,9.04.08

  33. Why  ?(common part) Themeson was proposed in the middle of 80’(Koch,Muller,Rafelski PR142,ShorPRL54) as one of the most promising QGP messengers because of the following reasons: • an enhancement of –meson, as well as other strange hadrons in QGP phase • interaction cross section is small and will keep information about the early hot and dense phase • meson spectrum is not distorted by feeddown from resonance decays • strangeness local conservation for  Stavinskiy,ITEP,9.04.08

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