1. December 10, 2003 Ivan Vitev 1 Jet Tomography Jet Tomography Ivan Vitev Iowa State University Iowa State University

2. December 10, 2003 Ivan Vitev 2 Outline of the Talk  Conclusions:  Properties of cold and hot nuclear matter  Evidence for the creation of the QGP at RHIC  Applications of Jet Tomography  Suppression of hadrons in semi-inclusive DIS  Jet quenching in hot nuclear matter, transverse momentum, centrality and rapidity dependence  Correlations and di-hadron tomography  Principles of Jet Tomography  Medium-induced gluon bremsstrahlung in QCD  Implementations of jet energy loss Ivan Vitev, ISU  Future Experimental Directions  Entropy growth, reappearance of the lost energy  Jet cone and intra-jet correlation studies

3. December 10, 2003 Ivan Vitev 3 Principles of Jet Tomography Ivan Vitev, ISU The QCD analogue of positron emission tomography Radionuclides: 11 C, 13 N, 15 O, 18 F Calibrated source Calculable absorption cross sections Interpretation of the results e+e+ e+e+ Prerequisites: e+e+

4. December 10, 2003 Ivan Vitev 4 Inclusive hadron distributions – calculable in perturbative QCD Ivan Vitev, ISU Leading order pQCD phenomenologyNext-to-Leading order pQCD 510 p T [GeV] Parton distribution functions Fragmentation functions Perturbative cross sections Calibrated Probes PHENIX Collab., Phys.Rev.Lett. 91 (2003) I.V., hep-ph/0212109 [in CERN Yellow report]

5. December 10, 2003 Ivan Vitev 5 Ivan Vitev, ISU M.Gyulassy et al., Nucl.Phys.B594 (2001); Phys.Rev.Lett.85 (2000) + + Exact algebraic recursion (Reaction operator approach) Effective 2D Schroedinger equation Path integral formulation R.Baier et al., Nucl.Phys.B 483 (1997); ibid. 484 (1997 ) B.Zakharov, JETP Lett. 63 (1996) U.Wiedemann, Nucl.Phys.B588 (2000) Radiative QCD Energy Loss Elastic energy loss Radiative energy loss J.D.Bjorken, SLAC preprint (1982) unpublished versus

6. December 10, 2003 Ivan Vitev 6 Gluon Absorption and Mass Effects Ivan Vitev, ISU Detailed balance significantly reduces energy loss for at RHIC E.Wang, X.-N.Wang, Phys.Rev.Lett. 87 (2001) M.Djordjevic, M.Gyulassy, nucl-th/0310076 Mass corrections and Ter-Mikayelian plasmon effect in QCD Reduction of E-loss Heavy quarks

7. December 10, 2003 Ivan Vitev 7 Modified Jet Cross Sections Ivan Vitev, ISU R.Baier et al., JHEP0109, (2001) Quenching factor Q(p T ) same as Leading parton R AA (p T ) g* g rad q Modified fragmentation functions Reduced partonic cross sections Typical LHC

8. December 10, 2003 Ivan Vitev 8 Effective Suppression of Fragmentation Functions Ivan Vitev, ISU C.Salgado, U.Wiedemann, Phys.Rev.Lett. 89 (2002) Kniehl, Kramer, Potter fragmentation functions z=p h /p c Independent Poisson approximation for multiple gluon emission Probability for fractional energy loss Normalized for suppressed leading hadrons (no feedback)

9. December 10, 2003 Ivan Vitev 9 Ivan Vitev, ISU DIS Tomography E.Wang, X.-N.Wang, Phys.Rev.Lett. 89 (2002) E’ E F.Arleo, Eur.Phys.J. C30 (2003) - radiative energy loss fraction - energy transfer

10. December 10, 2003 Ivan Vitev 10 Ivan Vitev, ISU QGP Tomography I.V., M.Gyulassy, Phys.Rev.Lett. 89 (2002) PHENIX Collab., Phys.Rev.Lett. 91 (2003) STAR Collab., Phys.Rev.Lett. 91 (2003) Absolute scale

11. December 10, 2003 Ivan Vitev 11 Centrality Dependence Ivan Vitev, ISU X.-N.Wang, nucl-th/0305010 G.G.Barnafoldi et al., hep-ph/0311343 Small number of semihard scatterings 1+1D GLV

12. December 10, 2003 Ivan Vitev 12 Rapidity Dependence Ivan Vitev, ISU 1+1D GLV (a double ratio) T.Hirano, Y.Nara, Phys.Rev.C68 (2003) Energy loss in a 3+1D hydro A.Adil, M.Gyulassy, I.V., in preparation

13. December 10, 2003 Ivan Vitev 13 g* g rad Di-Hadron Tomography Ivan Vitev, ISU q g rad QGP J.W.Qiu, I.V., Phys.Lett.B570 (2003) Di-jet acoplanarity (insufficient) Away-side quenching

14. December 10, 2003 Ivan Vitev 14 Ivan Vitev, ISU Near- and Far-Side Correlations T.Hirano, Y.Nara, Phys.Rev.Lett.91 (2003) Unaltered near-side correlations Disappearance of the away-side correlations K. Filimonov [STAR Collab.], DNP’03 meeting x y z Out-of-plane In-plane Trigger

15. December 10, 2003 Ivan Vitev 15 The “Remnants of Lost Jets” d+Au Ivan Vitev, ISU I.V., GLV e-loss simulation 4 GeV < p T tig < 6 GeV |y|<1 b=0 fm y=0 b=0 fm 100% recovered 600 MeV Reappearance of the lost energy Entropy growth Momentum sum rules S.Pal, S.Pratt, Phys.Lett.B574 (2003)

16. December 10, 2003 Ivan Vitev 16 Broadening of the Jet Cone Ivan Vitev, ISU C.Salgado, U.Wiedemann, hep-ph/0310079 Jet cone opening angle Intra-jet correlations - fraction of the total energy within a jet subcone Very small effect even at the LHC

17. December 10, 2003 Ivan Vitev 17 Summary of Dense Nuclear Matter SPS 2-3.5 0.8210-2401.5-2.51.4-2200-350 RHIC 7-10 0.6380-40014-206-7800-1200 LHC 17-28 0.2710-850190-40018-232000-3500 SPSRHIC LHC F.Karsch, Nucl.Phys.A698 (2002) Ivan Vitev, ISU DIS quenching0.50.12 Drell-Yan0.6 0.450.14 0.45 Cronin effect0.4-0.60.1-0.14 Th. estimate0.20.05 F.Arleo, hep-ph/0310274 [CERN Yellow Report] Hot versus cold nuclear matter Properties of Dense Nuclear Matter

18. December 10, 2003 Ivan Vitev 18 Conclusions Ivan Vitev, ISU  Significant theoretical advances in understanding non-Abelian bremsstrahlung: - Regimes far from asymptopia (E,L) relevant at RHIC - Incorporating mass and gluon absorption corrections  Jet tomographic analysis: - Cold nuclear matter - Suggests energy density at RHIC (static)  Future directions of high-p T studies in dense nuclear matter: - Correlations and jet structure, redistribution of - Quantitative studies of open charm and direct photons  Results from Jet Tomography correlated with other theoretical approaches are in strong support of the QGP paradigm at RHIC

19. December 10, 2003 Ivan Vitev 19 Conclusions Ivan Vitev, ISU  Significant theoretical advances in understanding non-Abelian bremsstrahlung: - Regimes far from asymptopia (E,L) relevant at RHIC - Incorporating mass and gluon absorption corrections  Jet tomographic analysis: - Cold nuclear matter - Suggests energy density at RHIC more that 100 times cold nuclear matter density  Future directions of high-p T studies in dense nuclear matter: - Correlations and jet structure, redistribution of - Quantitative studies of open charm and  Results from Jet Tomography correlated with other theoretical approaches are in strong support of the QGP paradigm at RHIC

20. December 10, 2003 Ivan Vitev 20 Discovery of “Jet Quenching” Ivan Vitev, ISU 0 1 2 pTpT

21. December 10, 2003 Ivan Vitev 21 Ivan Vitev, ISU The Phase Diagram of QCD 0200 400 600 100 200 300 0 Big Bang LHC RHIC SPS Quark-Gluon Plasma Color Superconductor Hadron Gas Chiral symmetry braking Quark pairing M.Stephanov,K.Rajagopal,E.Shuryak, Phys.Rev.Lett. 81 (1998)T.D.Lee, C.G.Wick, Phys.Rev.D 9 (1974) Chandra X-ray telescope CERN-SPS

22. December 10, 2003 Ivan Vitev 22 Energy Loss in Dense QCD Matter Ivan Vitev, ISU Elastic energy loss J.D.Bjorken, SLAC preprint (1982) unpublished Radiative energy loss Rather small to have significant observable effect QCD QED in the ability of the gluon to reinteract Landau-Pomeranchuk- Migdal effect in QCD M.Gyulassy, X.-N.Wang, Nucl.Phys.B420, (1994) I.Lokhtin, A.Snigirev in hep-ph/0310274 [CERN Yellow report] May be significant for large cone Parent parton Radiative gluon

23. December 10, 2003 Ivan Vitev 23 Ivan Vitev, ISU From Drell-Yan to DIS F.Arleo, Eur.Phys.J. C30 (2003) Gluon transport coefficient fixed from Drell-Yan Finite formation time Large number of scatterings approximation

24. December 10, 2003 Ivan Vitev 24 Ivan Vitev, ISU x y z Out-of-plane In-plane Trigger K. Filimonov [STAR Collab.], DNP’03 meeting p T trigger = 4-6 GeV/c 2 GeV/c < p T associated < p T trigger, |  |<1 Correlations with Respect to the Reaction Plane Very direct evidence for the path length dependence of