1 / 94

Jet Propagation and Mach-Cone Formation in (3+1)-dimensional Ideal Hydrodynamics

Jet Propagation and Mach-Cone Formation in (3+1)-dimensional Ideal Hydrodynamics. Barbara Betz Disputationsvortrag Johann Wolfgang Goethe-Universität Frankfurt am Main 13/10/2009. Phys. Lett. B 675 , 340 (2009), Prog. Part. Nucl. Phys. 62 , 556 (2009),

liz
Download Presentation

Jet Propagation and Mach-Cone Formation in (3+1)-dimensional Ideal Hydrodynamics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Jet Propagationand Mach-Cone Formationin (3+1)-dimensional IdealHydrodynamics Barbara Betz Disputationsvortrag Johann Wolfgang Goethe-Universität Frankfurt am Main 13/10/2009 Phys. Lett. B 675, 340 (2009), Prog. Part. Nucl. Phys. 62, 556 (2009), Phys. Rev. C 79, 034902 (2009), arXiv: 0907.2516 [nucl-th] (Nucl. Phys. A in press)

  2. The QCD Phase Diagram • proton • Insights into theory of strong interactions (QCD) • Medium created in heavy-ion (HIC) collisions similar to the one created after Big Bang • Explore the phase diagram of QCD with HIC hadronic phase and freeze-out expanding fireball initial state pre-equilibrium hadronization S. Bass, Talk Quark Matter 2001

  3. The Expanding Medium • From first principles, it is unclear if medium is … • „dust“ • fluid • Particles don‘t interact, • expansion independent • of initial shape • Particles interact, • expansion determined • by density gradient • Hydrodynamics: azimuthal anisotropy of • emitted particles, parametrized by v2 • Data described by hydrodynamics • Small • Medium behaves like an almost • ideal fluid P. Romatschke and U. Romatschke, Phys. Rev. Lett. 99,172301 (2007)

  4. 4 < pTtrigger < 6 GeV/c • pTassoc > 2 GeV/c STAR, Phys. Rev. Lett. 91 (2003) 072304 Jet - Studies in HIC I Trigger particle • Jet moving through dense matter, depositing its energy should eventually disappear • Jet suppression: signal for creation of opaque matter (Quark-Gluon Plasma) • Can energy lost by jets tell us something about medium properties?

  5. 4 < pTtrigger < 6 GeV/c • 0.15 < pTassoc < 4 GeV/c Au+Au / p+p = 200 GeV STAR, Nucl. Phys. A 774, 129 (2006) PHENIX, Phys. Rev. C 77, 011901 (2008) Jet - Studies in HIC II • Redistribution of energy to lower pT-particlesGeneration of Mach cone pattern • Re-appearance of the away-side for low and intermediate pTassoc • Mach cone angle sensitive to EoS: • Reflect interaction of jet with medium

  6. Hydrodynamics I • Medium created in a HIC can be described using hydrodynamics • Hydrodynamics represents (local) conservation of • energy-momentum • (local) charge • For ideal hydrodynamics in local thermodynamical equilibrium • , • , • , • Equation of State • For viscous hydrodynamics (Eckart frame) • ,

  7. Hydrodynamics II • Deriving the transport equations for viscous quantities up to 2nd order in • gradients, starting from the Boltzmann equation BB, D. Henkel and D. H. Rischke, Prog. Part.. Nucl. Phys. 62, 556 (2009) • W. Israel, J.M. Stewart, Ann. Phys. 118, 341 (1979) • W. Israel, J.M. Stewart, Ann. Phys. 118, 341 (1979) • A. Muronga, Phys. Rev. C 76, 014909 (2007) • A. Muronga, Phys. Rev. C 76, 014909 (2007) • BB, D. Henkel, and D. H. Rischke, Prog. Part. Nucl. Phys. 62, 556 (2009)

  8. STAR, Phys. Rev. Lett. 95, 152301 (2005) • Conversion into particles Freeze-out: Modelling of Jets • Jets can be modelled using (ideal) hydrodynamics: • residue of energy and momentum given by the jet • mainly flow driven • Assumption of • isochronous/isothermal freeze-out • No interaction afterwards

  9. Stopped Jet I • Applying a static medium and an ideal Gas EoS for massless gluons • Assume: Near-side jet is not modified by medium • Bragg Peak • Jet decelerates according to Bethe-Bloch formalism BB et al., Phys. Rev. C 79, 034902 (2009) • Mach cone • Diffusion wake • t=4.5/v fm

  10. Stopped Jet II BB et al., Phys. Rev. C 79, 034902 (2009) • Normalized, background-subtracted isochronous Cooper-Frye at mid-rapidity • pT = 5 GeV • Energy Flow Distribution • Assuming: Particles in subvolume will be emitted into the same direction Strong influence of the Diffusion wake

  11. P. Chesler and L. Yaffe, Phys. Rev. D 78, 045013 (2008) Modelling Jets using … • Energy density perturbation • Pointing vector perturbation • Strongly-coupled theory • AdS/CFT • v=0.75 • Energy density perturbation • Momentum density perturbation • Weakly-coupled theory • pQCD R. Neufeld et al, Phys. Rev. C 78, 041901 (2008) • v=0.99955 • Conclusion about Mach cones?

  12. Heavy Quark Jets in pQCD vs AdS/CFT • Compare weakly and strongly coupled models using heavy punch-through jet • Static medium and isochronous freeze-out needed for comparison BB et al., Phys. Lett. B 675, 340 (2009) • pQCD: Neufeld et al. source for a heavy quark R. Neufeld et al, Phys. Rev. C 78, 041901 (2008) • AdS/CFT: Stress tables with S. Gubser et al, Phys. Rev. Lett. 100, 012301 (2008) • t=4.5/v fm J. Noronha et al., Phys. Rev. Lett. 102, 102301 (2009) BB et al., Phys. Lett. B 675, 340 (2009) • No Mach-like peaks: • AdS/CFT: Strong influence of the Neck region • pT = 3.14 GeV

  13. Etot = 5 GeV • Jet 150 L. Satarov et al, Phys. Lett. B 627, 64 (2005) Expanding Medium I • Experimental results based • on many events • b=0 • Consider different jet paths A. K. Chaudhuri, Phys. Rev. C 75, 057902 (2007) , A. K. Chaudhuri, Phys. Rev. C 77, 027901 (2008) • Apply Glauber initial conditions and an ideal Gas EoS for massless gluons • Focus on radial flow contribution • Two-particle correlation (Tfreeze-out < Tcrit = 130 MeV): represents near-side jet

  14. Expanding Medium II BB et al., Nucl. Phys. A in press (arXiv:0907.2516 [nucl-th]) • Etot = 5 GeV pTtrig = 3.5 GeV • broad away-side peak • double peaked structure • due to • non-central jets PHENIX, Phys. Rev. C 77, 011901 (2008)

  15. Summary • Investigation of jet-medium interactions using (3+1)d ideal hydrodynamics for different energy and momentum loss scenarios (schematic source term, pQCD, AdS/CFT) • Diffusion wake is always created if dM/dx > threshold • Different impacts of pQCD and AdS/CFT source terms • Experimentally observed signal can be obtained from different contributions of several jets in an expanding medium Deflection of Mach cones Structure unrelated to EoS Single jet events • Transport equations for dissipative hydrodynamics to 2nd order in gradients Fundamental for any numerical application of viscous effects

  16. Backup

  17. Punch – Through Jet I • Applying a static medium and an ideal Gas EoS for massless gluons • Maximal fluid response • Assume: Near-side jet is not modified by medium BB et al., Phys. Rev. C 79, 034902 (2009) • v=0.999 • t=4.5/v fm

  18. Punch – Through Jet II BB et al., Phys. Rev. C 79, 034902 (2009) • Normalized, background-subtracted isochronous Cooper-Frye at mid-rapidity • pT = 5 GeV • Energy Flow Distribution • Diffusion wake causes • peak in jet direction • Assuming: Particles in subvolume will be emitted into the same direction

  19. Punch – Through Jet III BB et al., Phys. Rev. C 79, 034902 (2009) • Does the jet-pattern reproduce • the features of a Mach cone? • pT = 5 GeV • Velocity dependence of the • emission angle • Creation of Bow Shock for smaller v • strengthens peak in jet direction

  20. Punch – Through Jet IV • Transverse momentum deposition: • t=4.5/v fm BB et al., Phys. Rev. C 79, 034902 (2009) • Still influence of • diffusion wake • from explosion of • matter • Vorticity conservation

  21. Punch – Through vs Stopped Jet BB et al., Phys. Rev. C 79, 034902 (2009) • pT = 5 GeV • pT = 5 GeV • Punch-Through Jet • Stopped Jet • Similar freeze-out patterns

  22. Punch – Through Jet: Velocity Scan • t=4.5/v fm

  23. Near-side Jet • Assuming energy-momentum conversation and the disapparance of the near-side jet after t=0.5fm • t=4.5/v fm • Reduction of • diffusion wake • Not strong enough • to be seen in the • freeze-out pattern

  24. The Diffusion Wake G. Burau, Genua Harbour, September 2008 • The diffusion wake exists!

  25. Why linearized Hydro is not so good • Head wave pile-up • - Non-linear hydrodynamics • - Signal not well understood • - Non-Mach cone angle • Mach Cone • Linear hydrodynamics • Connected to EoS • Diffusion Wake • - Proportional to source • - Not seen experimentally • Source • - Non-linear hydrodynamics • - Non-thermalized

  26. Double-peaked structure visible for (dM/dx)/(dE/dx) 12.8% Momentum Deposition BB et al., J. Phys. G 35, 104106 (2008) • Static medium for different • energy and momentum loss • rates: • dE/dx = 1.4 GeV/fm • Cooper-Frye freeze-out • after t=7.2fm

  27. Stopped Jet • Jet stops after t=4.5/v fm BB et al., Phys. Rev. C 79, 034902 (2009) • tFO=4.5/v fm • tFO=6.5/v fm • tFO=8.5/v fm • Diffusion wake still present • Vorticity conservation

  28. Stopped Jet • Larger impact of thermal smearing • Diffusion wake causes • peak in jet direction BB et al., Phys. Rev. C 79, 034902 (2009) • tFO=4.5/v fm • tFO=6.5/v fm • tFO=8.5/v fm

  29. Different Contributions BB et al., Phys. Rev. C 79, 034902 (2009) • EMach 53.9% PxMach 6.5% • EDiff -12.3% PxDiff 18.7% • ENeck 57.4% PxNeck 73.7% • EHead 1.0% PxHead 1.0% • t=4.5/v fm • pT =2. 5 GeV

  30. Energy-Momentum Relation • general:

  31. Jet – Energy Loss Studies • Jet deposits energy and momentum along a trajectory • Applying linearized hydrodynamics J. Casalderrey-Solana et al., Nucl. Phys. A 774, 577 (2006) • Mach cone for • sound waves • Diffusion wake

  32. R. Fries et al, Phys. Rev. D 75, 106003 (2007) • Mach cone in coordinate space S. Gubser et al., Phys. Rev. Lett. 100, 012301 (2008) Jets in AdS/CFT I • Analogues: • Heavy Quark String • N=4 SYM Thermal Background Black hole in AdS space

  33. Diffusion Wake contribution • Pattern similar to pQCD Jets in AdS/CFT II • Energy density perturbation • Poynting vector perturbation P. Chesler and L. Yaffe, Phys. Rev. D 78, 045013 (2008) • Jet travelling at v=0.75 • Attention: No clear Mach cone signal

  34. Jets in AdS/CFT III • Non-Mach correlations • caused by Neck region J. Noronha et al., Phys. Rev. Lett. 102, 102301 (2009)

  35. Mach cone in coordinate space Jets in pQCD I • Considering a static medium and linearized hydrodynamics • for a punch-though jet R. Neufeld et al, Phys. Rev. C 78, 041901 (2008) • Mach cone signal & Diffusion Wake

  36. Mach cone in coordinate space Jets in pQCD II • Contour plots of magnitude of perturbed momentum density R. Neufeld et al., Phys. Rev. C 79, 054909 (2009) • Strong flow in jet-direction

  37. pQCD Source Term I • Idea: External color field generated by fast parton propagating through QGP • with • Lorentz forced • considered to lowest order in coupling g • Since

  38. pQCD Source Term II • For a parton moving with v=const. and omitting dielectric screening: • with

  39. pQCD Source Term III • For ultraviolett and infrared cut-off: • Ep energy of fast parton

  40. The Neck Zone in pQCD vs AdS/CFT • AdS/CFT • pQCD J. Noronha et al., Phys. Rev. Lett. 102, 102301 (2009) BB et al., Phys. Lett. B 675, 340 (2009) • Strong transverse flow • No strong • transverse flow

  41. t=4.5/v fm BB et al., Phys. Lett. B 675, 340 (2009) Heavy Quark Jets in pQCD vs AdS/CFT I • Idea: Compare weakly and strongly coupled models • Using heavy quark punch-through jet • Applying ideal hydrodynamics for a static • medium and an ideal gas EoS of massless • gluons • Assume that the near-side jet is not modified by the medium • pQCD: Neufeld et al. source for a heavy quark Neufeld et al, Phys. Rev. C 78, 041901 (2008) • AdS/CFT: Stress tables provided by S. Gubser, A. Yarom and S. Pufu with

  42. Heavy Quark Jets in pQCD vs AdS/CFT II BB et al., Phys. Lett. B 675, 340 (2009) • Normalized, background-subtracted isochronous Cooper-Frye at mid-rapidity • Isochronous freezeout needed to compare pQCD and AdS/CFT • No Mach-like peaks: • Strong influence of the Neck region • pT = 3.14 GeV J. Noronha et al., Phys. Rev. Lett. 102, 102301 (2009)

  43. Heavy Quark Jets in pQCD vs AdS/CFT III BB et al., Phys. Lett. B 675, 340 (2009) • Momentum Flow Distribution • Assuming: Particles in subvolume will be emitted into the same direction • Mach-like peaks & • Strong impact of diffusion wake • Independent of pT - cut

  44. Expanding Medium • Jet 90 • Jet 120 • Jet 180 • Jet 150

  45. Expanding Medium • Jet 120 • Jet 150 • Jet 180

  46. Expanding Medium • Etot = 5 GeV pTtrig = 3.5 GeV • broad away-side peak • double peaked structure PHENIX, Phys. Rev. C 77, 011901 (2008)

  47. Expanding Medium • Etot = 10 GeV pTtrig = 7.5 GeV • broad away-side peak • double peaked structure • due to • non-central jets • Strong impact of the Diffusion wake • Causes smaller dip for pT=2 GeV PHENIX, Phys. Rev. C 77, 011901 (2008)

  48. Expanding Medium • Etot = 5 GeV pTtrig = 3.5 GeV • broad away-side peak • broad away-side peak Pure energy deposition No conical distribution in expanding medium Jet 180: No peaks on away-side

  49. Expanding Medium • Etot = 5 GeV • Etot = 5 GeV • Etot = 10 GeV pTtrig = 3.5 GeV pTtrig = 3.5 GeV pTtrig = 7.5 GeV • en. and mom. loss • en. and mom. loss • pure energy loss

  50. Expanding Medium • Etot = 4.3 GeV pTtrig = 3.0 GeV • broad away-side peak • broad away-side peak

More Related