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Conjectured Phase Diagram

Acoustic scaling of anisotropic flow in shape-engineered events : implications for extraction ( μ B ,T) of the QGP Roy A. Lacey Stony Brook University. p. A Current Focus of our Field. Quantitative study of the QCD phase diagram. Conjectured Phase Diagram. Interest

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Conjectured Phase Diagram

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  1. Acoustic scaling of anisotropic flow in shape-engineered events: implications for extraction (μB,T) of the QGP Roy A. Lacey Stony Brook University Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  2. p A Current Focus of our Field Quantitative study of the QCD phase diagram Conjectured Phase Diagram • Interest • Location of the critical End point (CEP) • Location of phase coexistence lines • Properties of each phase • All are fundamental to the phase diagram of any substance Spectacular achievement: Validation of the crossover transition leading to the QGP  Necessary for the CEP? The extraction of transport coefficients is central to the heavy ion programs at RHIC and the LHC Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  3. Current Strategy Exploit system size and beam energy lever arm (,T) at freezeout Energy scan • LHC  access to high T and small • RHICaccess to different systems and • a broad domain of the (,T)-plane • RHICBESto LHC  360 increase • LHC + BES  access to an even broader domain of the (,T)-plane Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  4. Essential Questions Lacey et. al, arXiv:0708.3512(2008) Lacey et. al, Phys.Rev.Lett.98:092301 (2007) • ()-dependence of transport • coefficients , , etc? • The role of system size and • fluctuations? • Location of phase boundaries? • Indications for a CEP? At the CEP or close to it, anomalies in the dynamic properties of the medium can drive abrupt changes in transport coefficients Anisotropic flow is an invaluable probe DNP Fall Meeting, Roy A. Lacey, Stony Brook University, Oct. 25, 2013

  5. Reminder Observations η/s estimates – QM2009 • Excellent Convergence on • the magnitude of η/s at RHIC 4πη/s ~ 1 - 2 • T dependence of η/s? • μB dependence of η/s? • Possible signal for CEP? Status Quo A major uncertainty in the extraction of η/s stems from Incomplete knowledge of the Initial eccentricity εn – η/s interplay? Roy A. Lacey, Stony Brook University; QM11, Annecy, France 2011

  6. Status Quo Luzum et al. arXiv 0804.4015 Song et al Status Quo A major uncertainty in the extraction of η/s stems from Incomplete knowledge of the Initial eccentricity εn – η/s interplay? η/s is a property of the medium and should not depend on initial geometry! This is NOT an uncertainty; It is a failure of the method of extraction New methodology and constraints required DNP Fall Meeting, Roy A. Lacey, Stony Brook University, Oct. 25, 2013

  7. Essential message • Discovery of the acoustic nature of flow leads to specific scaling patterns which : • Give profound mechanistic insight on viscous damping • Provide constraints for • initial state geometry and its fluctuations • Extraction of the specific viscosity • (,T) dependence of the viscous coefficients • Hints for a possible critical point? This constitutes one of the most important recent developments in the field! Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  8. The Flow Probe Anisotropic p Idealized Geometry Isotropic p Yield(f) =2 v2cos[2(f-Y2] Crucial parameters Actual collision profiles are not smooth, due to fluctuations! Initial Geometry characterized by many shape harmonics (εn)  drive vn Acoustic viscous modulation of vn Staig & ShuryakarXiv:1008.3139 Initial eccentricity (and its attendant fluctuations) εndrive momentum anisotropy vnwith specific viscous modulation Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  9. Scaling properties of flow Initial Geometry characterized by many shape harmonics (εn)  drive vn (II) Scaling properties of flow Acoustic viscous modulation of vn Staig & ShuryakarXiv:1008.3139 Scaling expectations: n2 dependence vn is related to v2 System size dependence Each of these scaling expectations has been validated Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  10. Demonstration of acoustic scaling • What do we learn from these scaling patterns? Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  11. Geometric quantities for scaling Geometry 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. Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  12. Acoustic Scaling – n2 ATLAS data - Phys. Rev. C86, 014907 (2012) arXiv:1301.0165 • Characteristic n2 viscous damping validated • Characteristic 1/(pT)αdependence of extracted β values validated • Constraint for η/s and δf Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  13. Scaling properties of flow Acoustic Scaling – Centrality 5-70% • Eccentricity change alone is not sufficient • To account for the Npart dependence of vn • Transverse size () influences viscous damping • Characteristic scaling prediction is • non-trivial Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  14. Scaling properties of flow Acoustic Scaling – • Characteristic viscous damping validated • at RHIC & the LHC • A further constraint for η/s Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  15. Shape-engineered events Shape fluctuations lead to a distribution of the Q vector at a fixed centrality • Cuts on qn should change the magnitudes ,, at a given centrality due to fluctuations • Characteristic anti-correlation predicted for v3(q2) in mid-central events Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  16. Shape-engineered events ALICE data Shape fluctuations lead to a distribution of the Q vector at a fixed centrality q2(Hi) • Cuts on qn should change the magnitudes ,, at a given centrality due to fluctuations q2(Lo) • Viable models for initial-state fluctuations should still scale Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  17. Scaling properties of flow Acoustic Scaling of shape-engineered events • Characteristic viscous damping validated • for different event shapes at the same centrality • A further constraint for initial fluctuations model and η/s Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  18. Extraction of η/s Song et al • η/s show 100% uncertainty due to “uncertainty” about the • initial geometry • η/s is a property of the medium and should not depend on initial • geometry • This is NOT an uncertainty; It is an incorrect method of extraction Slope sensitive to 4η/s Characteristic viscous damping validated in viscous hydrodynamics;calibration  4πη/s ~ Extracted η/s value insensitive to initial conditions Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  19. Extraction of η/s arXiv:1301.0165 & CMS PAS HIN-12-011 Viscous Hydro Slope sensitive to η/s n2 scaling validated in experiment and viscous hydrodynamics; calibration  4πη/s ~ 2 Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  20. Anisotropy Measurements arXiv:1305.3341 CMS - Phys.Rev.C87, 014902 (2013) STAR - Phys.Rev.C86, 014904 (2012); Phys.Rev.C86, 054908 (2012) • An extensive set of measurements now span a broad range of beam energies (). Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  21. Scaling properties of flow Acoustic Scaling – 200 GeV 7.7 GeV 19.6 GeV 39 GeV 62.4 GeV 2.76 TeV • Characteristic viscous damping validated across beam energies • First experimental indication for η/s variation in the -plane Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  22. Summary Scaling properties of anisotropic flow lend profound mechanistic insights, as well as new constraints for transport coefficients What do we learn? • Flow is acoustic – “as it should be” • Obeys the dispersion relation for sound propagation • (n2& )  constraints for 4πη/s & viable initial-state models • 4πη/s for RHIC plasma ~ 1~ my 2006 estimate • 4πη/s for LHC plasma ~ 2 • Extraction insensitive to initial geometry model • Characteristic dependence of viscous coefficient β” on beam energy give constraints for: • ()-dependenceη/s • Indication for CEP?? Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  23. End Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  24. Geometric quantities for scaling Femtoscopic measurements • R_sidescales with R_bar for a broad range of system sizes and beam energies Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  25. Anisotropy Measurements High precision double differential measurements obtained for identified particle species at RHIC and the LHC. Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  26. Scaling properties of flow Acoustic Scaling – Ratios vn PID scaling Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  27. Essential Questions Luzum et al. arXiv 0804.4015 • LHC  access to high T and small • RHICaccess to different systems and • a broad domain of the (,T)-plane • RHICBESto LHC  360 increase Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  28. An Essential Question Song et al • Does the value of depend on the initial geometry model or the method of extraction? Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  29. Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  30. Data and calculated points from CMS PAS HIN-12-011 Viscous Hydro n2 scaling validated in viscous hydrodynamics; calibration  4πη/s ~ 2 Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  31. Viscous Hydro Viscous Hydro Characteristic viscous damping validated in viscous hydrodynamics; calibration  4πη/s ~ 1.3 Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  32. Validation of 1/R scaling Song et al η/s is a property of the medium and can not depend on initial geometry This is NOT an uncertainty; It is an incorrect method of extraction Slope sensitive to 4η/s Characteristic viscous damping validated in viscous hydrodynamics;calibration  4πη/s ~ Extracted η/s value insensitive to initial conditions DNP Fall Meeting, Roy A. Lacey, Stony Brook University, Oct. 25, 2013

  33. Acoustic Scaling – 1/R Compare system size @ RHIC Slope difference encodes viscous coefficient difference • Viscous coefficient larger for more dilute system Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  34. p Quantitative study of the phases of QCD is a central goal of our field • Interest • Location of the critical End point (CEP) • Location of phase coexistence lines • Properties of each phase • All are fundamental to the phase diagram of any substance Spectacular achievement: Validation of the crossover transition leading to the QGP  Necessary for the CEP? The extraction of transport coefficients is central to the heavy ion programs at RHIC and the LHC Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  35. Scaling properties of flow Acoustic Scaling – Ratios arXiv:1105.3782 The expected relation between vn and v2 is validated Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  36. Flow is partonic & Acoustic? arXiv:1211.4009 Note species dependence for all vn For partonic flow, quark number scaling expected  single curve for identified particle species vn Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  37. Anisotropy Measurements ATLAS data - Phys. Rev. C86, 014907 (2012) & ATLAS-CONF-2011-074 High precision double differential measurements obtained for higher harmonics at RHIC and the LHC. Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

  38. Anisotropy Measurements • Event-by-Event v2 measurements obtained via 2PC followed by unfolding. • v2 described by Bessel-Gaussian distribution: Contribution from mean geometry+fluctuations. Zimanyi Winter School, Roy A. Lacey, Stony Brook University, Dec.. 2 - 6, 2013

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