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In-Medium Studies of Omega, Nucleon and Open Charm with QCD Sum Rules. Ronny Thomas. Forschungszentrum Dresden-Rossendorf / TU Dresden. Dresden, September 2007. In-Medium Modification of Hadrons: , N, D QCD Sum Rules Four-Quark Condensates.
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In-Medium Studies of Omega, Nucleon and Open Charm with QCD Sum Rules Ronny Thomas Forschungszentrum Dresden-Rossendorf / TU Dresden Dresden, September 2007 • In-Medium Modification of Hadrons: , N, D • QCD Sum Rules • Four-Quark Condensates work with T. Hilger, S. Zschocke and B. Kämpfer supported by BMBF, GSI, EU, Helmholtz
Universal CONDENSATES , … ? | temperature > 0 density > 0 QCD Sum Rules QCD vacuum In-Medium Modifications Analogy: Stark & Zeemann effects
Chiral condensate Gluon condensate Zschocke et al (2002) (PCAC) Trace anomaly Mixed quark-gluon condensate Catalog of four-quark condensates …
„in-medium“ Nb (A=93) 0 0 LH2 (A=1) in medium CB-TAPS + A→ A‘ + (→ 0 + ) Trnka, Metag et al, PRL (2005) First moment: First moment • implies strong density dependence of specific four-quark condensate combinations RT, Zschocke, Kämpfer, PRL (2005) • change of QCD vacuum … Brown-Rho scaling ( In-medium shift HADES)
QCD Sum Rules Shifman, Vainshtein, Zakharov (1979) meson: Current-current correlator Dispersion Relation Operator Product Expansion (OPE) Hadronic side Next talk: T. Hilger Aspects of the OPE
Twice subtracted, Borel transformed dispersion relation Operator product expansion Wilson coefficients x CONDENSATES Ci small larger FOUR-QUARK CONDENSATES
Catalog of Four-Quark Condensates time, parity reversal invariance, … One flavor: FIERZ Vacuum: 5 Medium: 5+5 no inverse: nucleon Two flavors: but implies relations: Vacuum: 2•5 +10 = 20 Medium: 2•10+24 = 44 → flavor symmetry: 10 (20)
med 1 0 2 4 n / n0 1 Four-Quark Condensates Factorization and beyond: Chiral Symmetry: invariant → order parameter not V-A not invariant invariant N (vacuum) invariant
Nucleon in medium RT, Hilger, Kämpfer, NPA (2007) condensates Weighted dispersion relation condensates moments: Parametrization of hadronic side: →Sum rules in pole ansatz: Furnstahl, Griegel, Cohen, PRC (1992)
Analysis: Nucleon in medium four-quark condensates 3 coupled sum rule equations: * Drukarev et al, PRD (2003) ** Plohl, Fuchs, PRC (2006)
Scalar self-energy Numerical impact of density dependence of combined four-quark condensates: Vector self-energy
N Vector, scalar self-energies Analytical estimates: Example for fine-tuned set opposite effects In-medium Ioffe approximation:
Comparison: in medium Zschocke, Pavlenko, Kämpfer, PLB (2003)
Morath, Weise (2001) Hayashigaki (2000) ~ - ( 0 … 50 ) MeV ~ 30 … 50 MeV at saturation density ? Zschocke (2005) Open Charm: D CBM and PANDA @ FAIR D+ similar to K- - 80 MeV at saturation density Scheinast et al (KaoS), PRL (2006) D-,K+dc, us D meson in medium: D+,K-dc, us
Example of Operator Product Expansion for D-meson: amplifier mixing of QCD condensates under renormalization (Diploma thesis T. Hilger)
Conclusion • catalog of four-quark condensates • combinations of in-medium four-quark condensates: → strong density dependence N → some density dependence • different sum rules → no factorization of combined four-quark condensates → combinations like e.g. may serve as further order parameters of chiral symmetry breaking • further hadrons probe other condensates: D → CBM, PANDA Modified QCD vacuum
: Nucleon • interpolating field not unique • inclusion of derivatives Braun, Schäfer et al, PLB (1993) t = -1 Ioffe interpolating field: ci: (for vacuum)
Nucleon in vacuum Chiral condensate full QSR
QCD Sum Rules: 3 equations
← small impact 3 coupled sum rule equations weak density dependence of specific four-quark condensate combinations Gross-Boelting, Fuchs, Fäßler, NPA (1999) Drukarev, Fäßler et al, PRC (2004): • nucleon matrix elements of four-quark • operators for the nucleon structures • → weak density dependence Lattice: Göckeler, Schäfer et al, NPB (2002)
Analysis: Nucleon in medium Threshold dependence