1. Hydrodynamical Study of Jet Energy Loss Barbara Betz Institut für Theoretische Physik Johann Wolfgang Goethe-Universität Frankfurt am Main DPG - Frühjahrstagung Gießen 2007

2. Contents I.Introduction Jet Quenching Jet Quenching Two and Three Particle Correlations Two and Three Particle Correlations II.(3+1)d hydrodynamical approach Jet Implementation Jet Implementation III.Jet Evolution EoS with 1 st Order Phase Transition EoS with 1 st Order Phase Transition IV.Conclusion

3. Jet Quenching Suppression of the away-side jets Suppression of the away-side jets in Au+Au collisions in Au+Au collisions 4 < p T < 6 GeV/c 4 < p T < 6 GeV/c p T assoc > 2 GeV/c p T assoc > 2 GeV/c Compared to p+p collisions Compared to p+p collisions Jet Quenching J. Adams [STAR Collaboration], Phys. Rev. Lett. 91 072304 (2003)

4. Two Particle Correlation Redistribution of energy to low p T -particles: Redistribution of energy to low p T -particles: F. Wang [STAR Collaboration], Nucl. Phys. A 774, 129 (2006)  Sideward peaks  4 < p T < 6 GeV/c  0.15 < p T assoc < 4 GeV/c Peaks reflect interaction of jet with medium Peaks reflect interaction of jet with medium

5. Three Particle Correlation F. Wang [STAR Collaboration], preliminary F. Wang [STAR Collaboration], Nucl. Phys. A 774, 129 (2006)  1 =  ±     =  ±       = { 0 ±±±± 2

6. Mach Cone Speed of Sound F. Wang, QM06 Emission Angle of the Mach Cones cos θ = cscs v jet ~ 60 – 90° masseless QGP: c s ~ 0.57  masseless QGP: c s ~ 0.57 θ = 1.0 rad hadronic matter: c s ~ 0.3  hadronic matter: c s ~ 0.3 1 st order phase transition: c s ~ 0  1 st order phase transition: c s ~ 0 θ = 1.3 rad θ = 1.5 rad v jet depends on the mass of the leading quarks v jet depends on the mass of the leading quarks

7. Hydrodynamical Approach Barbara Betz, Kerstin Paech, Etele Molnar, Dirk Rischke, Horst Stöcker

8. (3+1)d Hydrodynamik Assume: Near-side jet not influenced by medium Assume: Near-side jet not influenced by medium Bag Model EoS Bag Model EoS Implement a jet that... Implement a jet that... deposits energy and momentum within 2 fm/c  deposits energy and momentum within 2 fm/c  in a spherically expanding medium 1 st order phase transition: Hadron Gas - QGP  1 st order phase transition: Hadron Gas - QGP  T c = 169 MeV

9. EoS with 1 st order phase transition t = 6.4 fm/c t = 9.6 fm/c t = 0 fm/c t = 12.8 fm/c

10. EoS with 1 st order phase transition At t = 0 fm/c medium is in the mixed phase At t = 0 fm/c medium is in the mixed phase t = 12.8 fm/c Sideward peaks appear at large angles t = 0 fm/c

11. Conclusion I. Two and Three Particle Correlations Sideward peaks appear and reflect Sideward peaks appear and reflect interaction of jet with medium and interaction of jet with medium and emission angle of mach cone emission angle of mach cone II. Hydrodynamical approach EoS with phase transition EoS with phase transition Sideward peaks appear at large angles Sideward peaks appear at large angles

12. Backup

13. Jet Propagation F. Wang, QM06

14. Energy Distribution Jet correlations in p+p collisions: Jet correlations in p+p collisions: Back-to-back peaks appear. Back-to-back peaks appear.

15. Energy Distribution Jet correlations in central Au+Au collisions: Jet correlations in central Au+Au collisions: Away-side jet disappears for particles with p t > 2 GeV/c Away-side jet disappears for particles with p t > 2 GeV/c

16. Energy Distribution Jet correlations in central Au+Au collisions: Jet correlations in central Au+Au collisions: Away-side jet (re)appears for particles with p T > 0.15 GeV/c. Away-side jet (re)appears for particles with p T > 0.15 GeV/c.