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Free Quarks and Antiquarks versus Hadronic Matter. Xiao-Ming Xu Collaborator: Ru Peng. Picture below T c. Critical temperature T c : transition between quark gluon plasma and hadronic matter Hadronic matter below T c : scatterings and flow of hadrons π, ρ, K, K * ,….
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Free Quarks and Antiquarks versus Hadronic Matter Xiao-Ming Xu Collaborator: Ru Peng
Picture below Tc Critical temperature Tc: transition between quark gluon plasma and hadronic matter Hadronic matter below Tc: scatterings and flow of hadrons π, ρ, K, K*,…
We propose new form of matter below Tc: free quarks, free antiquarks and hadrons
Medium effect Lattice QCD calculations give temperature-dependent quark-quark potential. Medium screening leads to weak binding of quarks. When temperature increases, the confinement potential gets weak and the bound state gets loose.
We expect Meson-meson collisions in high-temperature hadronic matter produce free quarks and antiquarks easily.
Cross Section meson-meson reaction
quark-quark potential Transition amplitude Mfi is derived from quark-antiquark wave functions and the quark-quark potential b(T)=0.35[1-(T/Tc)2] (Tc-T) (T)=0.28 (Tc-T) Tc=0.175 GeV, d=0.897 GeV mu=md=0.334 GeV, ms=0.575 GeV C.-Y. Wong, Phys. Rev. C65, 034902 (2002)
unpolarized cross section (1) LA=LB=0 (2) LA=0, LB0, SA=0 (3) LA=0, LB=1, SA=1, SB=1
master rate equation time evolution of number densities of , , K and K* in static hadronic matter
Ratios of number densities number density of hadronic matter nH n+n+nK+nK* Critical temperature Tc=0.175 GeV T (GeV) nq/nH at time t=0.5 fm/c 0.174 0.87 in the chiral limit 0.174 0.33 with the constituent quark mass 0.160.11 0.15 0.05 0.14 0.02
SUMMARY We have found: • an appreciable amount of free quarks and antiquarks produced by meson-meson reactions b. a new mechanism for deconfinement of quarks and antiquarks at high temperature. • new form of matter below Tc : free quarks, free antiquarks and hadrons. arXiv:0708.3804