1 / 41

Understanding deconfinement : new spectroscopy at T>Tc

Understanding deconfinement : new spectroscopy at T>Tc. Edward Shuryak Department of Physics and Astronomy State University of New York Stony Brook NY 11794 USA. Outline. The ``little bang” at RHIC => A strongly coupled QGP Lattice puzzles Hadrons above Tc Bound colored states

linore
Download Presentation

Understanding deconfinement : new spectroscopy at T>Tc

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. Understanding deconfinement: new spectroscopy at T>Tc Edward Shuryak Department of Physics and Astronomy State University of New York Stony Brook NY 11794 USA

  2. Outline • The ``little bang” at RHIC • => A strongly coupled QGP • Lattice puzzles • Hadrons above Tc • Bound colored states • AdS/CFT at finite T

  3. RHIC: a view from space • A dedicated collider for • Heavy ion collisions, AuAu 100+100 GeV/N • Polarized pp, • 250+250 GeV

  4. One of the first RHIC events at STAR detector, The average multiplicity at AuAu 200 GeV/N Is about 5000

  5. Spectra of various secondariesfrom all 4 detectors

  6. Main findings at RHIC • Particles are produced from matter which seems to be well equilibrated (by the time it is back in hadronic phase), N1/N2 =exp(-(M_1-M_2)/T) • Very robust collective flows were found, indicating very strongly coupled Quark-Gluon Plasma (sQGP) • Strong quenching of large pt jets: they do not fly away freely but are mostly (up to 90%) absorbed by the matter. The deposited energy seem to go into another hydrodynamical motion (conical flow)

  7. Reminder Statistical Model Works well with just two parameters Hadro-chemistry seems to be all done at the critical line

  8. Hydrodynamics is simple and very predictive <= only the EoS is needed,provided by the lattice (at finite T) Local Energy-momentum conservation: Conserved number: • Dynamic Phenomena • Expansion, Flow • Space-time evolution of • thermodynamic variables Caveat: Why and when the equilibration takes place is a tough question to answer

  9. Elliptic flow at RHIC Explosion goes in all directions Radial and especially Elliptic flow The red almond-shaped region is where the dense matter is. Yellow region shows “spectators” which fly by without interaction The so called “jet tomography” of the initial shape of the matter

  10. proton pion hydro describes both radial and elliptic flows(from Phenix) v_2=<cos(2 phi)> nucl-ex/0410003 Hydro models: Teaney (w/ & w/o RQMD) Hirano (3d) Kolb Huovinen (w/& w/o QGP)

  11. Sonic boom from quenched jets Casalderrey,ES,Teaney, hep-ph/0410067; H.Stocker… • the energy deposited by jets into liquid-like strongly coupled QGP must go into conical shock waves, similar to the well known sonic boom from supersonic planes. • We solved relativistic hydrodynamics and got the flow picture • If there are start and end points, there are two spheres and a cone tangent to both

  12. Distribution of radial velocity v_r (left) and modulus v (right).(note tsunami-like features, a positive and negative parts of the wave)

  13. PHENIX jet pair distribution Note: it is only projection of a cone on phi Note 2: more recent data from STAR find also a minimum in <p_t(\phi)> at 180 degr., with a value Consistent with background

  14. Collective flows =>collisional regime => hydrodynamics The main assumption: l << L (the micro scale) << (the macro scale) (the mean free path) << (system size) (relaxation time) << (evolution duration) I • In the zeroth order in l/L it is ideal hydro with a local stress tensor. • Viscosity appears as a first order correction l/L, it is inversely proportional to the cross section and thus is (the oldest) strong coupling expansion tool

  15. Viscosity of QGP QGP at RHIC seem to be the most ideal fluid known, its viscosity/(entropy density) =.1 -.2 water would not flow if only a drop with 1000 molecules be made 1st order correction to dist. fn.: :Sound attenuation length Velocity gradients D.Teaney(’03)

  16. What is needed to reproduce themagnitude of v2? Huge cross sections!!

  17. Charm transport (the diffusion coeff.)Moore&Teaney, hep-ph/0412346Mc/T=6-7 more collision needed for equilibration

  18. How to get 20 times pQCD s? (Zahed and ES,2003) • Quark-antiquark bound states don’t all melt at Tc (charmonium from lattice known prior to that…) • Many more colored channels • all q,g have strong rescattering qqbar  meson Resonance enhancements Huge cross section due to resonance enhancement causes elliptic flow of trapped Li atoms

  19. Resonance enhancement near zero binding lines provides large cross section(ES+Zahed,03) Well, it was shown to work for strongly coupled atoms

  20. Scattering amplitudesfor quasiparticlesM. Mannarelli. and R. Rapp hep-ph/05050080

  21. The coolest thing on Earth, T=10 nK or 10^(-12) eV can actually produce a Micro-Bang ! (O’Hara et al, Duke ) Elliptic flow with ultracold trapped Li6 atoms, a=> infinity regime The system is extremely dilute, but can be put into a hydro regime, with an elliptic flow, if it is specially tuned into a strong coupling regime via the so called Feshbach resonance Similar mechanism was proposed (Zahed and myself) for QGP, in which a pair of quasiparticles is in resonance with their bound state at the “zero binding lines”

  22. The new spectroscopy at T>Tc

  23. The QCD Phase Diagram The lines marked RHIC and SPS show the paths matter makes while cooling, in Brookhaven (USA) and CERN (Switzerland) T Theory prediction (numerical calculation, lattice QCD, Karsch et al) the pressure as a function of T (normalized to that for free quarks and gluons) Is it weakly coupled? Chemical potential mu

  24. lattice puzzles • it was recently found fom correlators (Asakawa-Hatsuda,Bielefeld) that J/,c dissolves in QGP only at T>(2-3)T_c.Why? • How can pressure be high at T=(1.5-2)T_c while q,g quasiparticles are quite heavy? Because the coupling is very strong! Because there also numerous bound states

  25. ``free energies” for static quarks (Karsch et al) • Upper figure is normalized at small distances: one can see that there is large ``effective mass” for a static quark at T=Tc. • Both are not yet the potentials! • The lower figure shows the effective coupling constant

  26. Fitting F to screened Coulomb • Fit from Bielefld group hep-lat/0406036 • Note that the Debye radius corresponds to • ``normal” (enhanced by factor 2) coupling, while the overall strength of the potential is much larger • It becomes still larger if V is used • instead of F, see later

  27. The potentials should have the entropy term subtracted,which makespotentials deeper still this is how potential I got look like for T = 1; 1.2; 1.4; 2; 4; 6; 10Tc, from right to left, from ES,Zahed hep-ph/0403127

  28. Here is the binding and |psi(0)|^2(J/psi puzzle resolved!) E/2M Vs T/Tc

  29. If a Coulomb coupling is too strong,falling onto the center may occur:but it is impossible to get a bindingcomparable to the massBut we need massless pion/sigma at T=>Tc ! • Brown,Lee,Rho,ES hep-ph/0312175 : near-local interaction induced by the ``instanton molecules” (also called ``hard glue” or ``epoxy”, as they survive at T>Tc • Their contribution is » |(0)|2 which is calculated from strong Coulomb problem

  30. Solving for binary bound statesES+I.Zahed, hep-ph/0403127 • In QGP there is no confinement => • Hundreds of colored channels must have bound states as well!

  31. The pressure puzzle is resolved!Masses, potentials and EoS from lattice are mutually consistent M/Tc vc T/Tc and p/pSB vs T/Tc

  32. Can we verify existence of bound states at T>Tc experimentally?Dileptons from sQGP:

  33. The widths are being calculated… But see, one can see peaks on the lattice Asakawa-Hatsuda, T=1.4Tc Karsch-Laerman, T=1.5 and 3 Tc

  34. A gift by the string theorists, the AdS/CFT correspondence, should help us understand sQGP

  35. QCD vs CFT: let us start with EoS(The famous .8 explained!)

  36. Strongly coupled CFT plasma is a very good liquid! • AdS/CFT calculation (D.Son et al 2003) of the correlator <Tmunu(x) Tmunu(0)> Via graviton propagator => viscosity/ (entropy density) => It is about as small as observed at RHIC!

  37. Bound states in AdS/CFT(ES and Zahed, PRD 2004) • The quasiparticles are heavy M_q =O(sqrt(lambda) T) >> T, exp(-M_q/T)<<1 • But there should be light binary bound states with the mass O(M_q/sqrt(lambda))=O(T) • Using Dirac/KG eqns with supercritical coupling one gets states falling on the center if l<sqrt(lambda) • But recent work on ``quarkonia” with D3D7 brane construction (e.g.M.Strassler et al 05) found that the s-wave states survive, with exactly the right mass O(M_q/sqrt(lambda))

  38. A complete ``gravity dual” for RHIC from 10-d GR? (ES,Sin,Zahed, in progress) • Black Holes + Howking rad. Is used to mimic the finite T • How black hole is produced can be calculated from GR (tHooft … Nastase) • Entropy production => black hole formation, falling into it is viscosity • Moving brane => hydro expansion

  39. QGP as a “matter” in the usual sense, not a bunch of particles, has been produced at SPS/RHIC It shows very robust collective flows. The EoS is as expected: but QGP seems to be the most ideal fluid known eta/hbar s=.1-.2 <<1 All of this hints that QGP is in a strong coupling regime, with new spectroscopy of colored states Interesting analogies with other strongly coupled systems ``quantum gases” AdS/CFT Conclusions

  40. Is such a sonic boom already observed?Mean Cs=.33 time average over 3 stages=> =+/-1.23=1.91,4.37 flow of matter normal to the Mach cone seems to be observed! See data from STAR, M.Miller, QM04

  41. Preliminary away <pT> dependence on angle (STAR,preliminary) <pT> (phi) has a dip structure in central AA. Mach shock wave?

More Related