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v n in relation to initial-state geometry and medium properties Roy A. Lacey Chemistry Dept.,

v n in relation to initial-state geometry and medium properties Roy A. Lacey Chemistry Dept., Stony Brook University. A central Issue. How to fully characterize of the QGP produced in RHIC & LHC collisions?. Characterization requires Development of experimental constraints

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v n in relation to initial-state geometry and medium properties Roy A. Lacey Chemistry Dept.,

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  1. vn in relation to initial-state geometry and medium properties Roy A. Lacey Chemistry Dept., Stony Brook University Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  2. A central Issue How to fully characterize of the QGP produced in RHIC & LHC collisions? • Characterization requires • Development of experimental constraints • for thermodynamic and transport coefficients • Development of quantitative model descriptions of • these properties Essential question: Do azimuthal anisotropy (vn) measurements provide constraints to nail down initial-state geometry & the transport properties of the QGP? T, cs, Focus  The role of scaling in answering this question! Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  3. A scenario for Azimuthal Anisotropy 4< pT <10 GeV/c Transition Region pT > 10 GeV/c Jet quenching pT < 4 GeV/c Flow Path length (∆L) driven Pressure driven (acoustic ) Both are linked by Geometry & interactions in the sQGP • This scenario implies very specific scaling properties which must be validated experimentally • Scaling validation  Flow and Jet Quenching provide straightforward probes of the QGP Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  4. The Flow Probe Idealized Geometry Control parameters Initial Geometry characterized by many harmonics Actual collision profiles are not smooth, due to fluctuations! Acoustic viscous damping Initial eccentricity (and its attendant fluctuations) εn drive momentum anisotropy vn with specific scaling properties Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  5. Radiative: Color charge scattering centers Range of Color Force Scattering Power Of Medium Density of Scattering centers Obtain via RAA measurements Jet quenching Probe Control parameters Suppression for ∆L Gyulassy, Wang, Müller, … Jet quenching drives RAA & azimuthal anisotropy with specific scaling properties Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  6. Geometric Quantities for scaling Phys. Rev. C 81, 061901(R) (2010) B A arXiv:1203.3605 σx & σy RMS widths of density distribution • Geometric fluctuations included • Geometric quantities constrained by multiplicity density. Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  7. Scaling properties of Jet Quenching Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  8. RAA Measurements - LHC Eur. Phys. J. C (2012) 72:1945arXiv:1202.2554 Centrality dependence pT dependence Specific pT and centrality dependencies – Do they scale? Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  9. Scaling of Jet Quenching arXiv:1202.5537 • RAA scales with L, slopes (SL) encodes info on • Compatible with the dominance of radiative energy loss Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  10. Scaling of Jet Quenching arXiv:1202.5537 • RAA scales as 1/√pT , slopes (SpT) encodes info on • L and 1/√pT scaling  single universal curve • Compatible with the dominance of radiative energy loss Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  11. High-pT v2 measurements arXiv:1204.1850 Centrality dependence pT dependence Specific pT and centrality dependencies – Do they scale? Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  12. Scaling of high-pT v2 arXiv:1203.3605 v2 follows the pT dependence observed for jet quenching Note the expected inversion of the 1/√pT dependence Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  13. Scaling of high-pT v2 arXiv:1203.3605 Combined ∆L and 1/√pT scaling  single universal curve for v2 Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  14. Jet suppression from high-pT v2 arXiv:1203.3605 Jet suppression obtained directly from v2 Rv2 scales as 1/√pT , slopes encodes info on Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  15. Scaling of Jet Quenching Phys.Rev.C80:051901,2009 arXiv:1202.5537 arXiv:1203.3605 • obtained from high-pT v2 and RAA [same αs]  similar • - medium produced in LHC collisions less opaque! Conclusion similar to those of Liao, Betz, Horowitz, Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  16. Scaling patterns of low-pT azimuthal anisotropy • Essential argument: • Flow is dominantly partonic • Flow is pressure driven (acoustic) • viscous damping follows dispersion relation • for sound propagation •  These lead to characteristic scaling patterns which must • be experimentally validated Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  17. Is hydrodynamic flow acoustic? εn drive momentum anisotropy vn with modulation Not analogous CBM Deformation Modulation  Acoustic Note:the hydrodynamic response to the initial geometry [alone] is included Characteristic n2 viscous damping for harmonics  Crucial constraint for η/s Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  18. Constraint forη/s & δf Deformation Characteristic pT dependence of β expected,  reflects the influence of δf Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  19. Is flow partonic? AMPT – Simulations with fluctuating initial conditions Deformation Characteristic scaling patterns are to be expected for the ratios of vn Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  20. Is flow partonic? AMPT – Simulations with (w) and without (wo) fluctuating initial conditions Deformation Characteristic scaling patterns are to be expected for identified particle species vn Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  21. vn(ψn) Measurements Phys.Rev.Lett. 107 (2011) 252301 (arXiv:1105.3928) v4(ψ4) ~ 2v4(ψ2) High precision double differential Measurements are pervasive Do they scale? Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  22. vn(ψn) Measurements ATLAS-CONF-2011-074 High precision double differential Measurements are pervasive Do they scale? Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  23. Flow is acoustic Deformation RHIC LHC Characteristic viscous damping of the harmonics validated  Crucial constraint for η/s Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  24. Acoustic Scaling β is essentially independent of centrality for a broad centrality range Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  25. Acoustic Scaling β scales as 1/√pT Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  26. Flow is partonic • Scaling for partonic flow validated for vn • Constraints for εn Similar scaling observed at the LHC Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  27. v3 PID scaling Flow is partonic Flow is partonic KET & scaling validated for v3  Partonic flow Flow is partonic STAR PHENIX Scaling for partonic flow validated for vn Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  28. Decoupling the Interplay between εn and η/s http://arxiv.org/abs/1105.3928 v3 breaks the ambiguity between MC-KLN vs. MC-Glauber initial conditions and η/s, because of the n2 dependence of viscous corrections Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  29. η/s estimates – QM2009 Good Convergence Conjectured Lower bound 4πη/s ~ 1 Temperature dependence Not fully mapped yet Much work remains to be done Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  30. Summary Remarkable scaling have been observed for both Flow and Jet Quenching They lend profound mechanistic insights, as well as New constraints for estimatesof transport and thermodynamic coefficients! What do we learn? • RAA and high-pT azimuthal anisotropy stem from the same energy loss mechanism • Energy loss is dominantly radiative • RAA and anisotropy measurements give consistent estimates for ˆq • The QGP created in RHIC collisions is less opaque than that produced at the LHC • Flow is acoustic • Flow is pressure driven • Obeys the dispersion relation for sound propagation • Flow is partonic • exhibits scaling • Constraints for: • initial geometry • η/s • viscous horizon • sound horizon Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

  31. End Roy A. Lacey, Stony Brook University; Ridge Workshop, INT, Seattle, May 7-11, 2012

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