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Jet Tomography of the Gluon Plasma at RHIC. nucl-th/0106072. QCD Motivation for A+A. Global Observables dN/dyd 2 p T , dE T /dyd 2 p T. Jet Quenching. Jet Tomography. 2/11/02 Iowa State. Miklos Gyulassy (Columbia Univ). RHIC Complex. 3.83 km circ. collider 6 intersection regions
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Jet Tomography of the Gluon Plasma at RHIC nucl-th/0106072 • QCD Motivation for A+A • Global Observables dN/dyd2pT, dET/dyd2pT • Jet Quenching • Jet Tomography 2/11/02 Iowa State Miklos Gyulassy (Columbia Univ) M.Gyulassy
RHIC Complex • 3.83 km circ. collider • 6 intersection regions • 4 Experiments • p+p, p+A, A+B • Energy: • 500 GeV for p-p • 200 GeV for Au-Au(per N-N collision) • Luminosity • Au-Au: 2 x 1026 cm-2 s-1 • p-p : 2 x 1032 cm-2 s-1(polarized) 6 3 5 1’ 4 1 2 M.Gyulassy
Approximate Boost invariance Si28 Ecm~100 AGeV Ag107 1050 M.Gyulassy
Rapidity and Proper Time Coordinates Bjorken: Boost Invariance=> DV = t Dy pR2 ~ 1D “Hubble” Expansion M.Gyulassy
Lattice QCD vs Ideal (Stefan-Boltzmann) Pressure Because QCD is Asymptotically Free JACEE ? F. Karsch et al M.Gyulassy
QCD Equation of State De~ 10-27 GeV/fm3 De~ 1 GeV/fm3 JACEE ? Lattice QCD, MILC 97 Bag Model E/VT4 3P/T4 T (GeV = 1013 K) M.Gyulassy
Mini-Bang at RHIC Au+Au 130AGeV How can we relate AA Experimental data to dense QCD Dynamics and Thermodynamics?? Nhadrons~4000 M.Gyulassy
Ions Approach t=-15 fm/c M.Gyulassy
Creation of Matter t=5 fm/c ?Quark GluonPlasma ? M.Gyulassy
Color White Hadronization t=10 M.Gyulassy
Global Constraints onInitial Conditions at RHIC Gluon Showers Soft vs Hard QCD Dynamics M.Gyulassy
Au197+ Au197--> ~5000 Ecm~200 AGeV SPS Si+Ag Npart Participating nucleons BRAHMS/RHIC 2001 700 5% 10% 20% dN/dy » 1.15 dN/dh b M.Gyulassy
dE/dx=2 GeV/fm No Jet Quenching Global Evidence for Gluon Showers at RHIC? X.N. Wang, MG, PRL86(01)3496 EKRT STAR PHENIX BRAHMS soft physics M.Gyulassy
Two Component Models • Soft Beam Jet Fragmentation • (string phenomenology, LUND, DPM) Npart(b)/2 X u ud ud u 2)Hard pQCD pT>p0(Pythia) x TAB(b) 3=1+2) Hard pQCD Hadronized by Strings u ud (HIJING) ud u A4/3 A1 M.Gyulassy
HIJING P0=2GeV XN Wang, MG Soft+Hard Dynamics in p+p HIJING= TAB(b)X [pQCD pt>p0]Pythia + Npart(b)X[Beam Jet Strings]LUND,DPM M.Gyulassy
g Nbinary Gluon Shadow g Jet Quenching PHENIX 01 Beam Jets u ud Npart/2 u ud PHOBOS BRAHMS XN Wang, MG P0=2GeV M.Gyulassy
XNWang, MG, PRL86(01)3496 PRL87:052301,2001 200 AGeV BRAHMS Initial Conditions from Centrality Dependence of dNch/dh Npart dNg(pT>2)/dy=200 HIJING ” rglue (t0=0.1 fm/c) » 10/fm3 dNg(pT>1)/dy=1000 EKRT ” rglue (t0=0.2 fm/c) » 25/fm3 M.Gyulassy
Jet Quenching Collective Flow STAR nucl-ex/0104006 PHENIX: nucl-ex/0109003 High pT Frontier at RHIC Four New Phenomena Discovered M.Gyulassy
Jets Vacuum QGP Rare Probes of Heavy Ion Collisions “Pio”sphere • Hard pQCD Probes: • Drell-Yan • Heavy Quarks (D, Y) • Direct g • Jets, high pT hadrons Z • Observables • dE/dx in QGP jet quenching • Deconfinement J/y suppression beams of hard probes: jets, J/y …. Jet Quenching can be used as a Tomographic Tool M.Gyulassy
Jet Tomography, GLVW jet g g g A+A Tomography with Jets X-ray Tomography M.Gyulassy
Jet Energy Loss and Tomography 1. GLV Formalism : P.Levai, I.Vitev,MG ``Non-Abelian energy loss at finite opacity,'‘ Nucl. Phys. B571 (2000) 197; Phys. Rev. Lett. 85, 5535 (2000) Nucl. Phys. B594, 371 (2001) ; nucl-th/0112071, nucl-th/0201078 2. Flavor Tomography: P.Levai, G.Papp, G.Fai, MG, ``Kaon and pion ratio probes of jet quenching '' nucl-th/0012017. “The pbar>pi- Anomaly at RHIC” I.Vitev, MG nucl-th/0104066 3. Azimuthal Tomography: I.Vitev,X.N.Wang,P.Houvonin,MG ``High pT azimuthal asymmetry in non-central A + A at RHIC,'' Phys.Rev.Lett.86:2537 (2001); Phys.Lett.B526:301(2002 ) Baier, Dokshitzer, Mueller, Schiff 1996- B.G.Zakharov 1996- U. Wiedemann 2000 M.Gyulassy
pQCD Known initial flux of q and g jets M.Gyulassy
MG, I Vitev, XN Wang, Phys.Rev.Lett.86:2537-2540,2001 M.Gyulassy
Discovery Jet Quenching at RHIC Au +Au -> p0 + X at Ecm= 130 AGeV Gabor David QM01 pQCD X TAB(b) PHENIX Central 10% PHENIX Peripheral80-95% M.Gyulassy
WA98 PbPb ->p0 160 AGeV In p+A Cronin pQCD X TAB(b) Pions alone p All charged hadrons p + K + p PHENIX: Phys.Rev.Lett.88:022301 (2002) M.Gyulassy
Central/Peripheral PHENIX M.Gyulassy
X.N.Wang Npart/2Nbin 4 A A Compare to Enhancement of High pT at CERN-SPS Pb-Pb • RAA exhibits amplified Cronin Enhancement at SPS energies RAA» (RpA )2 • Parton energy lossis overwhelmed by initial state soft multiple collisions at SPS! *dE/dx is small at SPS due to short plasma lifetime and low gluon density MG, Levai, Vitev, PRL85(00)5535 M.Gyulassy
How to extract gluon plasma density from Jet QuenchingPattern? M.Gyulassy
Quenched pQCD M.Gyulassy
Bjorken expansion Asymptotic Leading Log Approx GLV Opacity Expansion in LLA same as BDMS (mod Log E/m2L) Scaling Expansion For Bjorken 1+1D Expansion Transport Property Baier, Dokshitzer, Mueller, Schiff 1996 B.G.Zakharov 2000 U. Wiedemann 2000 M.Gyulassy
GLV vs LLA Debye screened g eff. g mass g g and g g g LLA Finite Ejet<20 GeV cannot be computed in leading log But can be computed numerically via GLV M.Gyulassy
Predicted Quench Pattern (GVW) M.Gyulassy
High pT BaryonDynamics at RHIC Pbar > p - for pT>2 GeV/c ?? S.Vance,MG Gluonic Junctions ? M.Gyulassy
Ivan Vitev, MG, nucl-th/0104066 Hydro pQCD Surprise: pbar > p- at high pT??? F. Messer, PHENIX J.Velkovska, PHENIX • Factor ~3 Quench of Pions • Possible novel baryon (junction) dynamics at high pT? S.Vance,MG M.Gyulassy
Veneziano,Rossi Baryon Junctions Meson = u u u u Baryon = Junction Baryon = Junction d d • Baryon transport dynamics (baryon junction) in rapidity y Kharzeev S.Vance,MG • We also expect enhanced pT slopes for • baryons from M.Gyulassy
Anomalous pbars Suppose there is a novel TB=400 MeV “Soft” B Component Vitev,MG M.Gyulassy
Charged Hadron versus Pion Quenching PHENIX data STARdata • Both STAR and PHENIX data are consistent with a factor of 2-3 suppression • of the high pT particle spectra. • The difference in the suppression of and inclusive charged hadrons can • be understood in a dual soft+hard model with baryon transport dynamics. • The extracted gluon rapidity density is dNg/dy~1000. M.Gyulassy
Azimuthal asymmetry of high pt particles *Finite dE/dx” v2(pt)™ 0forpt™ ¥ * f Solid: cylindrical geom Dasned: Wood Sax TAB Raimond Snellings MG, I. Vitev and X.N. Wang, PRL(01) M.Gyulassy
pT Barrel Plot CRAB NCG6571 pT pT 4 GeV V2 = 0 V2 = 0.2 Azimuthal Symm. Azimuthal Asymm. At RHIC M.Gyulassy
Summary • Global dN/dy( s,Npart ) are consistent with copious gluon showers 200<dNg/dy<1000 • Factor ~3 Suppression of pT>2GeV pions Tomography via Jet Quench => dNg/dy~1000 • New baryon transport dynamics revealed byp+/p+ & p-/p- >1 at Dy~5, DpT~3 GeV • Large 2 to 1 azimuthal asymmetry observed out to pT~ 6GeV! • Need higher pT data and p+A to confirm tomographic analysis => rglue~100 X rnuke reached at RHIC • Major Puzzles • Hydro works too well for pT<2GeV but STAR/PHENIX pp HBT inconsistent with Hydro and all current QGP tranport models: Rout=Rside=6fm indep of 1<Ecm<100! • dET/dNch independent of Ecm and Npart • Why v2 does not decrease with pT? M.Gyulassy
Jet quenching at RHIC (200 AGeV) versus LHC (5400 AGeV) • Increased quenching by a factor of • ~3 in the overlapping region • (roughly following the density) • ModeratepT dependence of the • quenching factor M.Gyulassy
Additional Effects that Influence E-Loss • Absorption effects – shown • to be negligible for E.Wang, X.N. Wang, PRL 87, 142301 (2001) (E-loss with detailed balance) • Multi-gluonfluctuations Q: is the difference between mean energy loss and multi-gluon fluctuations tractable M.Gyulassy, P.Levai, I.V. nucl-th/0112071 M.Gyulassy
Similar shape of the spectrum • Constantdensity renormalization • factror 1/Z=2-2.5 in a broad • pT>3 GeV range Additional Effects that Influence E-Loss • Include nuclear • shadowingfa/A(x,Q2). • Modification factor • taken as in HIJING • IncludekT smearingandCronin effect via • g(k) (assumed to be Gaussian) Same fit with Z~0.4-0.5!!! M.Gyulassy