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Probing Properties of QCD Matter with Strange and Heavy Quarks

Probing Properties of QCD Matter with Strange and Heavy Quarks. Huan Zhong Huang 黄焕中 Department of Physics and Astronomy University of California Los Angeles, CA 90095-1547 May 28-June 1, 2012, NN2012@San Antonio. Outline. Parton Degrees of Freedom from QCD Matter

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Probing Properties of QCD Matter with Strange and Heavy Quarks

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  1. Probing Properties of QCD Matter with Strange and Heavy Quarks Huan Zhong Huang 黄焕中 Department of Physics and Astronomy University of California Los Angeles, CA 90095-1547 May 28-June 1, 2012, NN2012@San Antonio

  2. Outline • Parton Degrees of Freedom from QCD Matter • Parton Energy Loss and Jet-Medium Interaction • Heavy Ion Collisions as Exotic Factory Facility • Outlook

  3. partonic hadronic A QCD Partonic Matter in Heavy Ion Collisions Properties of QCD Partonic Matter QCD Phases and Phase Boundary

  4. Image the drop after a time-of-flight v distribution from BE condensate drop !!

  5. Volcanic mediate pT – Spatter (clumps) An Equilibrated Partonic System L X W Use coalescence picture to study partons at the phase boundary 5

  6. W and f are special • – (sss) state; m = 1672.45 MeV • f -- (ss) state; m = 1019.456 MeV Strange quark constituents produced in collisions No decay feeddown contributions Small hadronic re-scattering cross sections Messengers from quark-hadron phase boundary !

  7. Strangeness from Bulk Partonic Matter RCP X L Constituent Quark Number Scaling -- Hadronization through quark clustering -- Effective DOF – constituent quarks quasi-hadrons at Tc ? Lattice QCD picture? W f(ss) 7

  8. Parton PT Distributions at Hadronization If baryons of pT are mostly formed from coalescence of partons at pT/3 and mesons of pT are mostly formed from coalescence of partons at pT/2 • and f particles have no decay feeddown contribution ! • decay contribution is small These particles have small hadronic rescattering cross sections 8

  9. Strange and down quark distributions s distribution harder than d distribution perhaps related to different s and d quarks in partonic evolution Independent Test – f/s should be consistent with s quark distribution Yes ! 9

  10. Test on s/d Quark Ratios s/d quark ratios = W/X = X/L yes! but with large uncertainties due to decay feeddown corrections in L 10

  11. Effective Parton Distribution in the QM Drop at Hadronization L Parton Spectroscopy at RHIC X W f Use particle emission to measure partonpT distribution and angular anisotropy (v2) in the dense parton drop !! More theoretical development – He, Fries and Rapp, Phys.Rev. C82 (2010) 034907

  12. RHIC Beam Energy Scan Program RHIC BES data: 39.0, 11.5, 7.7 GeVAu+Au year 2010 27.0, 19.6 GeVAu+Au year 2011 -- Is there a transition from parton dominated matter to hadronic matter in the RHIC low energy region? -- Possible Structure of QCD phases – critical point? 12

  13. phi meson v2 deviates from partonic picture @ 11.5 GeV • π+, K0S, p, Λ and Ξ- approximately follow one common curve • -mesons @ 11.5 GeV does not follow the trend of other hadrons. Mean deviation from the other distribution: 2.6 σ

  14. W/f ratios @ 11.5 GeV also deviates from 39-200 GeV What is the collision energy where the deviation from partonic dominated matter becomes eminent? -- 2011 data from 19.6 and 27.0 GeVAu+Au collisions -- Perhaps more scan between 11.5 and 19.6 needed

  15. Ratio of anti-Omega/Omega S quarks are pair-produced: why are there NET baryon numbers in W? Any dynamical process responsible for the baryon number transport? Direct Transport Through Gluon Junctions … W + K + K + K + (X) Note the anti-Lambda/Lambda ratio is much smaller where u/d quarks can carry the net quark number from baryon number stopping ! 15

  16. Ratios of anti-L/L and anti-X/X at mid-rapidity Solid red: STAR BES Solid blue: STAR published Open blue: NA49 Baryon dynamics important at low beam energy collisions

  17. Intriguing Features for Baryon Rich Matter Baryon and anti-baryon v2differences: ~10% at higher energiesincrease dramatically @ 7.7 and 11.5 GeV Chiral magnetic wave? Baryon transport? Hadronic potential?

  18. pT Scales and Physical Processes RCP Three PT Regions: -- Fragmentation -- multi-parton dynamics (recombination or coalescence or …) -- Hydrodynamics (constituent quarks ? parton dynamics from gluons to constituent quarks? )

  19. Jet – Medium Interactions Leading particle jet energy loss Jet and/or medium induced particle emission (trigger) Near-Side Away-Side Trig-hadron angular correlations Df = ftrig-fhadron

  20. Conic Emission or V3 Initial Geometry More particles are emitted in a cone direction on the away-side !! Dynamics: Mach cone effect from supersonic jets passing thru the medium? Gluon radiation? parton scattering? Geometry: v3 initial state Use Heavy Quarks!! pTtrig= 2.5-4.0 GeV/c; pTasso= 1.0-2.5 GeV/c Au+Au Mark Horner (for STAR Collaboration): J. Phys. G: Nucl. Part. Phys. 34 (2007) S995

  21. How does the dense medium couple to heavy quarks ? Does heavy quark participate in bulk collective flow ? thermalization of quarks/gluons Does heavy quark jet-medium interactiongenerate broad away-side emissions? Trigger on non-photonic electrons from heavy quark decays

  22. Non-photonic electron -- hadron correlation 3 < pTtrig< 6 GeV/c & 0.15 < pTasso< 0.5 GeV/c dAu • Away side for d+Au is fit well by p+pPYTHIA • The Cu+Cu and Au+Au data cannot match the PYTHIA result – there is an away side broadening STAR Preliminary STAR Preliminary 0-20 % CuCu 0-20% AuAu

  23. V2 and RAA are Related Precise value of v2 at pT> 6, 10 GeV/c ? RAA at pT > 10 GeV/c at RHIC should RAA approach unity at higher pT ? Future measurements will shed more lights on possible physical scenarios for parton energy loss dynamics ! Heavy Quarks will be special -- Lorentz g dependence on partonELoss on jet-medium interaction near-side vs away-side?

  24. Features of Partonic Matter Central Au+Au Collisions at RHIC Bulk Partonic Matter -- 1) parton collectivity, multi- parton dynamics coalescence/recombination 2) v2 and pT distributions for effective quarks -- evolution from gluons – constituent quarks 3) Intriguing dynamics of baryon rich matter at low energy L X W 4) Major shift in DOF between 11-39 GeV?!

  25. Remarks on Parton E Loss Parton Energy Loss  Hadron PT Scale > 5-6 GeV/c Intrinsically a Dynamical Evolution System (path length?) ! -- Rapid Decrease of Energy Density with Evolution Time -- Even partons originated from the center of the hot/dense fireball may escape Theoretically Eloss calculations – dynamic issue simultaneous calculation of RAA and v2 at high pT !! Medium Response to Jets Plowing Through -- Heavy quark interactions with medium - non-photonic electron – hadron correlations - D – h correlations -- Separate Charm and Bottom energy loss – Heavy Flavor Tracker Upgrade– F. Videbaek’s talk!

  26. Potential exotic particles/phenomena: penta-quark states (uudds, uudds!) di-baryons H – (L-L, uuddss) [W-W] (ssssss) strange quark matter meta-stable Parity/CP odd vacuum bubbles disoriented chiral condensate …… Discoveries from Unexpected Areas?! RHIC -- Frontier for bulk partonic matter formation (quark clustering and rapid hadronization) -- Factory for exotic particles/phenomena STAR’s capability has been enhanced greatly with recent upgrades !! 26

  27. Search for di-hyperons and study hyperon-hyperon interactions from correlation measurement • The scattering length (a0) and the effective range (reff) with no, weak, medium, and strongcoupling to -N : a0 (fm) reff (fm) No coupling -2.42 -6.36 weak (Set.A) -2.47 -6.65 medium (Set.B) -2.98 -13.53 strong (Set.C) -2.27 -2.61 • Current fit parameters is consistent with non-existence of a strongly bound state of  • 0-40% Au+Au @ 200 GeV STAR Preliminary Set A – Weak N coupling Set B – Medium N coupling Set C – Strong N coupling Fit A. Ohnishi and T. Furumoto

  28. RHIC – a dedicated QCD Facility Having a great run! Even greater potential for future discoveries ! (Deconfinement Phase Transition) AA Exotic AA pA pp pp pA (CGC,EMC) (spin)

  29. End

  30. Volcanic high pT -- Strombolian eruption Volcanic mediate pT – Spatter (clumps) Volcanic low pT – Bulk matter flows Nucleus-Nucleus Collisions and Volcanic Eruption 30

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