Sticky Quark-Gluon-Molasses in collaboration with G.E. Brown, M. Rho, E. Shuryak NPA 740 (2004) 171 hep-ph/ ; hep-ph/ Quest for new states of matter at RHIC Chang-Hwan Lee & Hong-Jo

My main works before Pusan - Kaon Condensation in Neutron Star (Ph.D.) Astro-Hadron Physics - Evolution of Neutron Stars and Black Holes [ CH Lee, Physics Reports 275 (1996) 255 ] - Kaon production in Heavy Ion Collisions [KaoS] [ Li, Lee, Brown, PRL 79 (1997) 5214 ]

March 2003

Heavy Ion Physics in Pusan since 2003 Theory : CH Lee Hong-Jo Park (Ph.D. student) Eun-Seok Park (Master student) Experiment : IK Yoo et al.

T Density Hadrons Neutron Star Early Universe RHIC K bound system Scaling Mesons from NS to RHIC Quark-Gluon-Molasses

 Brown/Rho Scaling  Vector Manifestation [Harada/Yamawaki/Rho..]  Dilepton Experiment: rho-meson mass drops.  Kaon production in heavy ion collisions [KaoS]  Kaon condensation: kaons are condensed in neutron stars due to dropping kaon mass. Scaling Meson : previous works by Korean collaborations New Recent Developments

p + e - p + K - Kaon Condensation: previous works Kaon effective mass e - chemical potential density M reduce pressure forming denser medium M NS,max = 1.5 M sun “ Maximum mass of NS = 1.5 solar mass ” is still consistent with all the binary radio pulsars.

new developments: Kaonic Nuclear Bound States  Is kaon-nuclear attraction is strong enough to make kaon condensation ? Yamazaki et al. (2003)

3 He 3 HeK - Antisymmetric Molecular Dynamics Method Isovector Deformation Dote et al. 2002

PLB 597 (2004) 263 Total binding energy : 194 MeV from K - ppn Mass = 3117 MeV, width < 21 MeV

Kaonic Nuclei - Mini Strange Star  deep discrete bound states: with binding energy ~ 100 MeV  Strong in-medium KN interactions.  Precursor to kaon condensation. Very strong K - -p attraction

Scaling Mesons in Neutron Stars After Recent New Observations  Isolated Single Neutron Stars  Binary Neutron Stars Kaon Condensation still open possibility !

Scaling Mesons below Tc Vector Manifestation [Harada/Yamawaki/Rho … ] - When chiral symmetry is restored (at Tc) - Renormalization Group Fixed Points give us Vanishing pi, rho mass Vanishing coupling

TcTc    A1A1 M ? Brown/Rho scaling Q: What happens at RHIC/LHC whey they cross Tc ? Vector Manifestation RG fixed point Vanishing coupling ! Rho/Harada/Sasaki RHIC LHC

Braun-Munzinger, Stachel, Wetterich (2003)  Chemical freezeout temperature is close to Tc.  Equilibration in the chirally broken sector just below Tc.  “ rho/pi ” ratio was lower than STAR experiment roughly by a factor of 2 Equilibrium of hadronic mode has to be already established above Tc at RHIC ! [ Below Tc, coupling vanishes ! ] Our point of view

Questions  RHIC: Can hadronic modes survive after phase transition ?

Prejudice saves time for thinking ! Our Principle We may be biased, but

Unorthodox phase structure (working hypothesis)  pion, sigma masses go to zero at T = Tc;+: smooth phase transition (2 nd order) QGP Sticky QGM Mesons disappear TcTc T zb    A1A1 M 2m q * qq

What is (perturbative) QGP above Tc ?  weakly interacting regime: weak running coupling.  quarks are not locked into hadrons.  quarks, antiquarks & gluons are proper thermodynamic variables Q) Have we really seen QGP at RHIC ? Our Answer is “ No ” ! at RHIC, it is believed that T>Tc has been reached.

 RHIC data is consistent with ideal hydrodynamics.  It is the most perfect liquid known: viscosity/entropy (  /s) = 0.1 (much less than that of most liquids, e.g.  /s=1 for He 4 at high pressure, 40 for water)  Matter formed at RHIC is not weakly interacting quasi-particle gas. Motivation RHIC: beyond phase transition

Hydro vs RHIC data [Teaney et al.]

Hydrodynamical expansion of trapped Li 6 What happened at RHIC ? Hydrodynamical Expansion Elliptic Flow

Question  Why does the matter formed at RHIC behaves as a nearly ideal fluid ?  What is the matter formed at RHIC ?  Because it’s in a very strong coupling regime  We named it “Sticky Quark Gluon Molasses” It is not a plasma !

Running coupling at large diatance Lattice Calculation by F. Zantow et al. (Bielefeld) Strong coupling regime above Tc

Are there hadrons above Tc ?  Old point of view: most hadrons including J/  melt there.  Brown, Lee, Rho, Shuryak [NPA 740 (2004) 171]: quark-antiquark bound states exists above Tc including low-mass pionic modes.

New Idea  at T>T c the color charge continues to run to larger values, stopped by the Debye screening only when  s = 0.5 is reached.  quark-antiquark bound states exist for T c < T < T zerobinding due to relativistic effects + spin- spin interaction + nonperturbative 4- point NJL-type interactions.

Unorthodox phase structure (Hypothesis)  pion, sigma masses go to zero at T = Tc;+: smooth phase transition (2 nd order) QGP Sticky QGM Mesons disappear TcTc T zb    A1A1 M 2m q * qq

2 nd order phase transition Q: Can we make low-mass bound states above Tc ? We have only partial answers, but working on the problem

Our toy model (combined with lattice results) thermal mass from lattice Klein-Gordon equation Assumption strong coupling regime ?

Color Coulomb interaction  solve Klein-Gordon equation in relativistic regime

4 -point Interaction (NJL type: Instantons ?) BGLR: Phys. Rep. 391 (2004) 353 Lattice + NJL

ss  E Coulomb sqrt( )  E 4-point Binding energies at Tc (slightly above) in GeV, fm unit * M q = 1 GeV (extrapolation from LGS) is used. Binding energy from Color Coulomb & 4-point interaction is enough to make massless bound states

What the lattice free energy tell us ? Still on-going, but we are finding similar results in collaboration with F. Zantow (Bielefeld Group)

Potential extracted from Free energy [Bielefeld] closed : data open: fitting

Binding energy from 2-body potential Thermal mass dependence Bound state disappear

Mass of bound states with 2-body interaction Not enough binding yet !

What has to be done in the (near) future ? Better understanding of thermal masses above Tc ? 4-point interactions ? Dileptons from RHIC ? Baryons ? High pt particles ? …….

 Matter formed at RHIC is not perturbative QGP (weak coupling), but is in a strong coupling regime.  All s-wave mesons do not melt at Tc, but at higher temperature, i.e., zero binding lines.  Hadronic masses (for sigma, pi, rho, A1) goes to zero both below and above Tc. Working Hypothesis as Conclusions RHIC found “sticky quark gluon molasses” instead of QGP !

For the Future of Korea-EU ALICE Collaboration “ Alice wonderland ” is one of the best place where physicists, astrophysicsists, cosmologists, and astronomers can work together. Simple-minded theorist ’ s point of view Key words: early universe, quarks, gluons, QGP, dense matter, dense stellar matter, neutron stars, … …