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High Multiplicity Study

High Multiplicity Study. E.Kokoulina, A.Kutov for SVD-2 Collaboration JINR, Russia & GSTU, Belarus. ISMD 2007, LBNL Berkeley, August, 4-9. OUTLINE. Introduction Gluon Dominance Model (e + e - , pp, pA, pp) “Thermalization” project status Outlook. _.

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High Multiplicity Study

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  1. High Multiplicity Study E.Kokoulina, A.Kutov for SVD-2 Collaboration JINR, Russia & GSTU, Belarus ISMD 2007, LBNL Berkeley, August, 4-9

  2. OUTLINE • Introduction • Gluon Dominance Model (e+e-, pp, pA, pp) • “Thermalization” project status • Outlook _ ISMD 2007, LBNL Berkeley, August, 4-9

  3. Introduction We use the unified approach to the multiplicity description at HEP. It is based on essentials of QCD and on the main experimental phenomena in multiparticle dynamics. We are interested the high multiplicity (HM) region: n > n(s). _ ISMD 2007, LBNL Berkeley, August, 4-9

  4. Introduction pQCD & hadronization V. Kuvshinov, E.K. Acta Phys.Polon. B13 (1982). - annihilation proton (nucleus) collisions Soft Photons proton-antiproton- annihilation THERMALIZATION project ISMD 2007, LBNL Berkeley, August, 4-9

  5. Gluon Dominance Model (GDM): e+e- annihilation Second stage (hadronization): BD Firststage(cascade):a) gluon fission; b) quark bremsstrahlung; c) quark pair creation. quark fission -> NBD Convolution: of two stages ISMD 2007, LBNL Berkeley, August, 4-9

  6. GDM: e+e- - annihilation Pn Pn H(q) 161 GeV 22 GeV 161 GeV q n n Pn in -annihilation at 22 (TASSO) and 161 GeV (OPAL) ; H(q) at 161 GeV. E. K. Minsk, NPCS (2002)]; ISMD32,2002. ISMD 2007, LBNL Berkeley, August, 4-9

  7. GDM: e+e- - annihilation • - maximal (average) multiplicity of hadrons from one gluon while its passing through of hadronization is constant -> fragmentation mechanism of hadronization (one to one) • gluon hadronization is softer than quark one: ISMD 2007, LBNL Berkeley, August, 4-9

  8. GDM: pp - interactions • After an inelastic collision of two protons the part of energy are converted into the thermal (the dissipating energy) and one or few gluons become free • Gluons may give cascade • Some of gluons (not of all) leave Quark-Gluon System (QGS) – are evaporated and are converted to hadrons. 1st stage 2ndstage ISMD 2007, LBNL Berkeley, August, 4-9

  9. GDM: pp - interactions Our model study had shown:quarks ofinitial protons are stayingin leading particles (from 70 to 800 GeV/c). Multiparticle production (MP) is realizedbygluons*). We name them active ones. _________________________________________ *The dominance role of gluons at multiparticle production (MP) was proposed S.Pokorski and L. Van Hove (1975), P. Carruthers (1984). ISMD 2007, LBNL Berkeley, August, 4-9

  10. GDM: pp - interactions • Scheme with the branch of gluon in QGS (TSMB) • Scheme without the gluon branch (TSTM) E.K. and V.Nikitin. 7th Int. school-seminar The actual problems of Microworld Physics, Gomel, Belarus. 1 (2004) ISMD 2007, LBNL Berkeley, August, 4-9

  11. GDM: pp – interactions (scheme with branch) • MD of active gluons at the moment of impact (Poisson) • MD of branch gluons (Furry) for the first scheme • MD at the hadronization stage (BD) ISMD 2007, LBNL Berkeley, August, 4-9

  12. GDM: pp – interactions (scheme with branch) - ratio of evaporated gluons to all active ones; gluon hadronization parameters on second stage; N ~40.This value is very likely to the number of partons in the glob of cold QGP, which leads to production of soft photonexcess. P.Lichard & L.Van Hove. Phys.Let. B245 (1990) 605. ISMD 2007, LBNL Berkeley, August, 4-9

  13. pp –interactions (scheme without branch) After evaporation gluons leave QGS and fragment to hadrons. MD is convolution Poisson and BD 69 GeV/c 800 GeV/c E.K. Acta Phys.Polon. B35(2004)295 ISMD 2007, LBNL Berkeley, August, 4-9

  14. pp –interactions (without branch) ISMD 2007, LBNL Berkeley, August, 4-9

  15. Hadronization Mechanisms • recombination mechanism • clan as independent intermediate gluon source B.Muller [nucl-th/0404015] Fragmentation: Recombination: ISMD 2007, LBNL Berkeley, August, 4-9

  16. pp – interactions(neutral) MD of π0 at 69 Gev/c Limits to max charged, neutral & total multiplicities (26, 16, 42). Mean multiplicity of π0 versus the number of nch V. Grishin. Phys.El.Part.and At.Yad. 10 (1989)689. • gluon hadronization parameters for π0 • Centaur (yes, HM region), AntiCentaur (no) • particle number limits ISMD 2007, LBNL Berkeley, August, 4-9

  17. pp – interactions(ISR, 30-60 GeV) Clan (cluster) superposition consisting from one, two (or more) gluon fission Pn 62 GeV Soft ( ) & semi-hard ( ) components, and so on. n E.K., Nikitin V. et al. ISHEPP2004. ISMD 2007, LBNL Berkeley, August, 4-9

  18. pp(nucleus) – interactions (h/ ratio) Au-Au 200 GeV/N, peripheral (60-92%). PHENIX. Nucl.Phys.A757(2005). GDM: pp PHENIX GDM h/for pp: 70 GeV/c = 1.19+/-0.25 ,,, 800 GeV/c = 1.49+/-0.33 … 62 GeV ~ 1.6 ( ). • the dominance of active gluon plenty in nucleus central collisions leads to the new kind matter formation –QGP • agreement with h/ ratio ISMD 2007, LBNL Berkeley, August, 4-9

  19. Soft photons (SP excess) Measured SP: σ(SP) are 5-8 times larger than expected ones from QED. Assumption: QGS or excited new formed hadrons set in almost equilibrium state during a short period. That is why we use the black body emission spectrum: ISMD 2007, LBNL Berkeley, August, 4-9

  20. Soft photons (SP excess) The number of SP is estimated by MVB density ρ(T )=n(T)/V: • estimation of SP emission region • SP excess is the sign of hadronization M.Volkov,E.K., E.Kuraev. Part. & Nucl. Let., 5 (2004)122 ISMD 2007, LBNL Berkeley, August, 4-9

  21. _ pp – annihilation (experiment) J.Rushbrooke & B.Webber. Phys.Rep. C44(1978)1. 32, 100 GeV/c ISMD 2007, LBNL Berkeley, August, 4-9

  22. _ GDM: pp – annihilation Experiments(10-100 GeV/c): a tendency to the production of leading mesons. f2 behavior explanation. The simple scheme with appearance at first moment of m active gluons. GF and f2 : E.K. AIP. 828 (2006) 81 ISMD 2007, LBNL Berkeley, August, 4-9

  23. _ GDM: pp – annihilation GDM includes intermediate quark topologies at the initial stage making only from valent quarks (“0”-, “2-”) or valent and vacuum ones (“4-”, “6-”). MD are superposition of them. (“0”) + + (“2”) + + (“4”) + + + +… ISMD 2007, LBNL Berkeley, August, 4-9

  24. _ GDM: pp – annihilation Pn 14.75 GeV/c • intermediate topology superposition • hadronization predominance at annihilation ISMD 2007, LBNL Berkeley, August, 4-9

  25. project “THERMALIZATION” SVD-2 Collab.: Belarus, Czech Republic, Russia, Slovak Republic, Ukraine Scientific programme:multiparticle dynamics study in p+p(A) interactions with HM (n>20) at IHEP U-70. Micro strip VD, 10000 channels. Č 10 m target Drift tubes tracker, 2400 channels Magnetic spectrometer DeGa V.V.Avdeichikov et al. JINR-P1-2004-190, Proposal ”THERMALIZATION”. SVD-2 setup ISMD 2007, LBNL Berkeley, August, 4-9

  26. Project “THERMALIZATION 20 elements: triangle h=18, thickness 1.8 mm Trigger scintillation hodoscope (“camomile”) for theregistration of rare events with HM: Liquid hydrogen target ISMD 2007, LBNL Berkeley, August, 4-9

  27. project “THERMALIZATION” • Search for & new collective phenomena study: • BEC of identical particles. • Ring events (Cerenkov gluon). • Soft photon cross section. • Grouping of secondary. ISMD 2007, LBNL Berkeley, August, 4-9

  28. project “THERMALIZATION” 1) M.I.Gorenstein & V.V.Begun, BITP, Ukraine [hep-ph/0611043]: at HM the experimental manifestation of BEC may be founded by the sharp increase of neutral meson multiplicity fluctuations at fixed total multiplicity. ISMD 2007, LBNL Berkeley, August, 4-9

  29. project “THERMALIZATION” 2) RUN 2002: Ring event search[Seminar NPCS,Minsk,2006]. Preliminary 4) RUN 2002: the indication to the grouping of secondary in the certain direction[Hep-ph/0612364] Preliminary ISMD 2007, LBNL Berkeley, August, 4-9

  30. project “THERMALIZATION” pSi pPb pC RUN 2002 MD in pC, pSi and pPb ISMD 2007, LBNL Berkeley, August, 4-9

  31. project “THERMALIZATION” Alignment taskof detectors is an essential step in the track reconstruction: before after 2006 data ISMD 2007, LBNL Berkeley, August, 4-9

  32. project “THERMALIZATION” Z, mm X, mm Y, mm ISMD 2007, LBNL Berkeley, August, 4-9

  33. “THERMALIZATION” n=22 ISMD 2007, LBNL Berkeley, August, 4-9

  34. “THERMALIZATION” Preliminary Preliminary Integrated MD for X, Y planes Multiplicity distributions for X and Y planes (n_beam<5) ISMD 2007, LBNL Berkeley, August, 4-9

  35. Outlook • Data pA (Si,C, Pb) 2002 run will be study • A set of pp data in 2007-2009 runs will be obtained. • We expect interest phenomena in the HM region will be got. ISMD 2007, LBNL Berkeley, August, 4-9

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