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HIGH challenges in LOW energy HADRON physics. G. Vesztergombi. Zimanyi School Budapest, 25 November 2008. OUTLINE. AA Landscape STAR plans pp,pA -Static quarks -High pT below 20 GeV -NA61 -CBM -QGP in pp -Barion versus parton propagation. AA. pp,pA.
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HIGH challenges in LOW energy HADRON physics G. Vesztergombi Zimanyi School Budapest, 25 November 2008
OUTLINE • AA • Landscape • STAR plans • pp,pA • -Static quarks • -High pT below 20 GeV • -NA61 • -CBM • -QGP in pp • -Barion versus parton propagation
Science 21 November 2008: Vol. 322. no. 5905, pp. 1224 – 1227 Ab Initio Determination of Light Hadron Masses S. Dürr,1 Z. Fodor,1,2,3 J. Frison,4 C. Hoelbling,2,3,4 R. Hoffmann,2 S. D. Katz,2,3 S. Krieg,2 T. Kurth,2 L. Lellouch,4 T. Lippert,2,5 K. K. Szabo,2 G. Vulvert4 More than 99% of the mass of the visible universe is made upof protons and neutrons. Both particles are much heavier thantheir quark and gluon constituents, and the Standard Model ofparticle physics should explain this difference. We presenta full ab initio calculation of the masses of protons, neutrons,and other light hadrons, using lattice quantum chromodynamics.Pion masses down to 190 mega–electron volts are used toextrapolate to the physical point, with lattice sizes of approximatelyfour times the inverse pion mass. Three lattice spacings areused for a continuum extrapolation. Our results completely agreewith experimental observations and represent a quantitativeconfirmation of this aspect of the Standard Model with fullycontrolled uncertainties. Latest in LATTICE QCD
PENTA ? All baryonic states listed in PDG can be made of 3 quarks only * classified as octets, decuplets and singlets of flavour SU(3) * Strangeness range from S=0 to S=-3 • A baryonic state with S=+1 is explicitely EXOTIC • Cannot be made of 3 quarks • Minimal quark content should be , hence pentaquark • Must belong to higher SU(3) multiplets, e.g anti-decuplet observation of a S=+1 baryon implies a new large multiplet of baryons (pentaquark is always ocompanied by its large family!) important Searches for such states started in 1966, with negative results till autumn 2002[16 years after 1986 report of PDG !] Searches were for heavy and wide states
Motivation for new measurements below = 20 GeV Practically no high or medium Pt data between Einc = 24 and 200 GeV Mysterious transition around 80-90 GeV: convex versus concave spectra Energy threshold for Jet-quenching? Emergence of Cronin-effect in pA interactions is completely unknown energy dependence centrality dependence particle type dependence particle correlations Production of Upsilon (9.5 GeV) particles near the threshold.
Beier (1978) NA49 (CERN) results at 158 FODS (IHEP) at 70 GeV
Pb+Pb, 0-12.7% most central p+Pb reference preliminary CRONIN-effect removed by p+A baseline RA+A/p+A NEW !!! WA98 and NA49 data presented in QM'06 by Gianluca USAI's plenary talk
SPOKESPERSON: Marek GAZDZICKI SPOKESPERSON: Gyoergy VESZTERGOMBI GLIMOS: Zoltan FODOR Beam: Approved: 21-FEB-07 Status: Preparation NA61 Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at the CERN SPS (Technical coordinator) CERN Greybook 2008
Benchmark NA49pp at E = 158 GeV 30 events/spill Events Energy > 3 GeV/c > 4 GeV/c > 5 GeV/c 2 106 158 100 1 0.01 Estimates with the assumption 1011 proton/sec 109 interaction/sec 1 day=1014 158 5 109 5 107 5 105 CBM Perspectives Suppression 10-1 10-2 10-3 1 day=1014 90 5 108 5 105 500 20 day=2 1015 90 1010 107 104 Suppression 10-3 10-6 10-10 20 day=2 1015 45 107 10 0 For symmetric nuclei max energy 90/2 assumed
Special requirements for Y-> e+e- and high pT Extremely high intensity - Pile-up Segmented multi-target - Relaxed vertex precision Straight tracks - High momentum tracks DREAM: 109 interactions/sec
Átlag pT (Van Hove) Multiplicity Részecskeszám (Van Hove)
Single FIRE-BALL = QGP? (AB)* A B
Double FIRE-BALL = Factorization? B* A B A*
BARION propagation through the NUCLEUS A N** N* A* A** N
Npart = 3+1 Ncoll = 3 HADRON PROPAGATION
Npart/2 = (13+12)/2 =12.5 Ncoll = (36+28)/2 = 32 HADRON PROPAGATION (Some diffractive binary collisions included)
PHENIX 200 GeV Au-Au Ncoll = 1 d-Au d-Au Npart =Ncoll Au-Au Npart = 1
Earlier Cronin-effect at higher energies: 2 -> 1 GeV/c Pizero smaller Cronin-effect.