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Meson mass in nuclear medium. Su Houng Lee Thanks to: Hatsuda + former collaborators + and to Kenji Morita(GSI) and Taesoo Song(A&M) Phase transition, order parameter and nuclear matter Light quark system (Few comments on theory and recent experiments)
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Meson mass in nuclear medium Su Houng Lee Thanks to: Hatsuda + former collaborators + and to Kenji Morita(GSI) and Taesoo Song(A&M) Phase transition, order parameter and nuclear matter Light quark system (Few comments on theory and recent experiments) Heavy quark system (Few comments on recent theory and outlook)
EOS: e , p Quark number cq Lattice results for phase transition in QCD (from Karsch’s review) Heavy quark V(r) Confinement: L=e-F Chiral sym: <qq> Susceptibility cmqcL
G0 <a/p B2>T <a/p E2>T G2 Local operator related to confinement? Gluon Operators near Tc • Two independent operators Gluon condensate or Twist-2 Gluon • At finite temperature: from
<E2>, <B2> vs confinement potential • Local vs non local behavior Time W(ST)= exp(-s ST) OPE for Wilson lines: Shifman NPB73 (80) T S W(S-T) = 1- <a/p E2> (ST)2 +… W(S-S) = 1- <a/p B2> (SS)2+… Space W(SS)= exp(-s SS) Space • Behavior at T>Tc W(SS)= exp(-s SS) <a/p B2>T W(ST)= exp(-g(1/S) S) <a/p E2>T
Local operators in Nuclear Medium • Linear density approximation • Condensate at finite density • At r = 5 xrn.m.
Nuclear medium : partially deconfined and chiral symmetry restored QCD vacuum
Light quark system • Many review: Hayano, Hatsuda, arXiv:0812.1702 • Here, • Few comments on momentum dependence • Few comments on two recent experiments
Hadronic world : Spontaneously broken chiral symmetry • Order parameters • Hadronic world Ds1(2460) D1(2420) D(2400)? Ds(2317) 348 413 349 530 ? D*(2112) D*(2007) Ds(1968) D(1870) 144 137 0- 0+ 1- 1+ 0- 0+ 1- 1+
Few comments on vector meson mass shift from QCD sum rules • Vacuum saturation hypothesis ( Hatsuda & Lee92 ) For r meson For A1 meson For j meson Can such signal survive trivial smearing effects ?
Importance of momentum dependence (Lee98) L T • T, L components in vector meson q • Momentum dependence n.m. To be safe, |q|<0.5 GeV Or Separate measurement of L, T component 3x n.m.
Example: momentum dependent Medium width • Width with constant cross section w, k b n • Width for momentum dependent cross section
Few comments on Experiments outside Japan • CBELSA/TAPS PRL 94 (05) : w mass reduction 16% CBELSA/TAPS Recent reanalysis: background generated from pp, ph 4 g events, omitting 1 g more subtraction blow 700 MeV • CLAS: no mass shift observed, but qr > 0.8 GeV
Heavy quark system • Comments on heavy quark system near Tc • In nuclear matter
Few things to note about J/y near Tc • Tc region is important in HIC Au+Au 200 Agev, b=0 T (GeV) t (fm/c) • Large non-perturbative change at Tc (e-3p)/T4 T/Tc • Resumed perturbation fails Karsch hep-lat/0106019
<a/p B2>T <a/p E2>T Approach based on OPE • Separation of scale in this approach Non perturbative perturbative • In this work, • J/y mass shift (Dm) near Tc: QCD 2nd order Stark effect • J/y width (G) near Tc : perturbative QCD + lattice • check consistency of Dm , G at Tc :QCD sum rules • Application to nuclear matter
= Mass shift: QCD 2nd order Stark Effect : Peskin 79 e > Lqcd • OPE for bound state: m infinity • Attractive for ground state
2nd order Stark effect from pNRQCD • LO Singlet potential from pNRQCD : Brambilla et al. 1/r > Binding > LQCD, • Derivation • Take expectation value • Large Nc limit • Static condensate • Energy •
Thermal width from NLO QCD + confinement model Summary • Elementary sJ/y in pert QCD, LO (Peskin + others) and NLO (Song, Lee 05) LO NLO • Thermal width: sJ/y x thermal gluon (Park, Song, Lee, Wong 08,09)
Confinement model: Schneider, Weise • E,B Condensate
D M y / J GeV Mass and width of J/y near Tc (Morita, Lee 08, M, L & Song 09) Summary Dm from QCD Stark Effect G =pert QCD + confinement model
Constraints from QCD sum rules for Heavy quark system • sum rule at T=0 : can take any Q2 >=0, Phenomenological side OPE r J/y Y’ s
QCD sum rule constraint (Morita, Lee 08) G [MeV] G [MeV] Dm [MeV] Dm [MeV] Can also use Borel sum rule
D M y / J GeV G Mass and width of J/y near Tc (Morita, Lee 08, M, L & Song 09) Summary Dm from QCD Stark Effect QCD sum rule limit with DG =0 G =constraint-Dm (Stark effect) G =pert QCD + confinement model
NLO QCD + confine-model G in NLO QCD + confinement model Summary • Non perturbative part at Tc: confinement model (mg(T) C(T)) Constraints from Borel sum rule • From Tc to 1.05 Tc mass and width seems to rapidly change by 50 MeV ; to probe higher temperature within this region, • For mass, need higher dimensional operators • For width, Need higher twist contribution
Two places to look Reconstruction of Imaginary Correlator and RAA from RHIC
Y’ Reconstruction of Imaginary correlator • Imaginary correlator r J/y w m S0 • Reconstructed correlator
2-comp model (Rapp) Comparison with experimental data of RHIC (√s=200 GeV at midrapidity)T. Song, SHLee (preliminary) Melting of y’ cc Slope: GJ/y Melting T of J/y Height: mass of J/y
Effects of width and mass Assumed recombination effect to be the same Mass shift by -100 MeV • At LHC
Anti proton Heavy nuclei Expected luminosity at GSI2x 1032cm-2s-1 Observation of Dm through p-A reaction at PANDA Can be done at J-PARC
Summary • Nuclear matter: non trivial change characteristic of QCD phase transition • To see Vector meson mass shifts, they have to be produced almost at rest to avoid trivial smearing effect 3 Nuclear matter also cause J/y, cc to change mass of 7, 15 MeV . Larger effect for y(3686), y(3770) 4. Such effects could be searched at FAIR, J-PARC