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The Space-Time Puzzle at RHIC Instead of slowly burning QGP Log Dt~ R/v def >>R Evidence for Sudden freezeout Dt << R ! Amazingly independent of 1< KE cm < 100 AGeV Yet there is Huge v 2 ~0.15 out to 6 GeV, transverse flow , hadro equilibration, pbar > pi-, …. q. Y-Axis. Y-Axis.
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The Space-Time Puzzle at RHIC • Instead of slowly burning QGP Log Dt~R/vdef >>R • Evidence for Sudden freezeout Dt << R ! • Amazingly independent of 1< KEcm< 100 AGeV • Yet there is Huge v2~0.15 out to 6 GeV, transverse flow , hadro equilibration, pbar > pi-, …
q Y-Axis Y-Axis P 1 K P 2 Source X-Axis X-Axis Beam Axis Z-Axis Z-Axis AGS-SPS-RHICPion Interferometry • Central AuAu (PbPb) • Why saturation? • Why no rise in space or temporal homogeneity? STAR Preliminary
M. Lisa et al., PRL 84, 2798 (2000) R. Soltz et al., to be sub PRC C. Adler et al., PRL 87, 082301 I.G. Bearden et al., EJP C18, 317 (2000) Amazingly Weak Energy dependence p- • Rout and Rside are energy independent within error bars. • Smooth energy dependence in Rlong • No immediate indication of very different physics • Fit Rlong to: • AGS: A = 2.19 +/- .05 • SPS: A = 2.90 +/- .10 • RHIC: A = 3.32 +/- .03
HBT radii at 2 AGeV M. Lisa
qS=47° qS=33° qS=37° y z z y y z x x ’ x x ’ x ’ x similar to naïve overlap: b~5 fm 3 fm Images of p--emitting sources (scaled ~ x1014) 2 AGeV 4 AGeV 6 AGeV Large, positive tilt angles
Hydro+UrQMD Soff, Bass, Dumitru (PRL 86) Amazing! PHENIX and STAR at RHIC
Deflagration (Q->H Burn Front) vdef~dH/4dQ Dt~R/vdef IFF Qout Qside Why we expected more Rout>>Rside ? t Combustion Theory Van Hove (83) GKMS (84) Hadron Gas QGP x PION INTERFEROMETRY OF QUARK - GLUON PLASMA. By S. Pratt (Minnesota U.). 1986. Published in Phys.Rev.D33:1314-1327,1986 PION INTERFEROMETRY IN ULTRARELATIVISTIC HEAVY ION COLLISIONS. G. Bertsch, M. Gong, M. Tohyama, Phys.Rev.C37:1896-1900,1988.
QGP EOS Continuous Cross Over vs First Order Bag Model Equation of State D. Rischke , MG, NPA 613(97)397
The QGP Stall t~R QGP Stall e0=20 GeV/fm3 evolved with hydro DT=0 P=e/3 D. Rischke, MG NPA 613(97)397
Pratt-Bertsch Cpp(qside,qout) qside P=e/3 DT/Tc=0 DT/Tc=0.1 Side Out qout D. Rischke, MG, NPA 613(97)397
ppRout/Rside QGP-> Pions QGP->Resonances DT=0 P=e/3 DT=Tc/10 D. Rischke, MG NPA 613(97)397
Effect of Rapid Thermalization Tf=Tc NULL Solutions!! QGP-> Pions QGP->Resonances
Dissipative Hadronic FSI distort pion lenses Soff, Bass, Dumitru nucl-th/0012085 • long-lived dissipative hadronic phase dominates correlation signal • dissipative hadronic phase: unavoidable consequence of thermalized QGP IF strong incoherent resonance dynamics applies
Predicted B.R. Schlei (QM 99) nucl-th/9904067
The Thorn in Hydro’s side See D. Teany, E. Shuryak
Useful cartoon showing why HBT in AA is not easy to unfold P.Kolb, U. Heinz MANY 8D xm-pn correlated geometries give same HBT radii
P.Kolb, U. Heinz Hydro (x,y,t,K) Correlated Geometries
Rside Rout Rlong Rout<Rside is possible Denes Molnar’s Parton Cascade Diffuse correlated geometries xside xout
Are Systematic Experimental Errors Under Control? Corrections P.Filip ??
More work on Coulomb correction needed Better to show Uncorrected data and compare to corrected theory ! P.Filip
Systematic Theory HBT Errors p Wigner Wavepacket x See also S. Pratt … Padula,Gavin MG NPB 329 (90) 357 Classical Transport Theory
However, Rlong is tooo longg! Hydrodynamic HBT is surprisingly good agreement with Rout,side ! Given D. Teany, E. Shuryak
New Attemps at sudden hadronization: Non-equilib Polyakov V(L) L(A) But does this really solve Rlong Is short? U.Heinz Is it consistent with small e-b-e fluctuations?
Closing Remarks: (Sorry no time for Event-by-Event fluct) • RHIC HBT has posed a serious thorn in theory side • V2, flow, hadron ratios are consistent with EULER hydro • up to pT~2 GeV, but hydro fails at AGS, SPS • Yet HBT pattern is ~uniform in energy • High pt>2GeV tails reveal jet quenching through • very dense opaque matter • Yet hadronization is of short duration • (only marginally consistent with hydro Rout,side) • Bjorken flow seems dead with short Rlong! • Is Landau resurrecting? • Are we on wrong hydro/transport track? • Non-equilib classical fields? Inhomogeneous turbulence? • Also need to go back to basics and review HBT assumptions