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An EFT around Fermi surface. Chaejun Song(SNU & PNU) with M. Harada, C. Sasaki (Nagoya), D.-P. Min (SNU), T.- S. Park (KIAS). hep-ph/0410124. T(MeV). Early Universe (RHIC). Quark-Gluon Plasma. ~150. Phase Transition. Color Superconductor Neutron Star. Hadron Gas. ~10.
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An EFT around Fermi surface Chaejun Song(SNU & PNU) with M. Harada, C. Sasaki (Nagoya), D.-P. Min (SNU), T.- S. Park (KIAS) hep-ph/0410124
T(MeV) Early Universe (RHIC) Quark-Gluon Plasma ~150 Phase Transition Color Superconductor Neutron Star Hadron Gas ~10 Density(n0) Nuclear Phase Diagram Atomic Nuclei
Pions in medium kaons in medium Hadrons in Medium
Heavy Baryon Chiral Effective Theory • Very powerful for a system of a few baryons • Systematic expansion with Q/ • Applications to nuclear matter -> new scale appears! • Purpose: study dense medium in a systematic way
Our scales • Small scale Q: excitation scale from Fermi surface (or pion mass) • Large scale : chiral symmetry breaking scale • Intermediate scale : Fermi momentum
Expansion scales • Q/ • /
Analogy from HDET See D.K. Hong: PLB 473, 118 (00)
1-loop: . Axial Vector Correlator
Pion Decay Constants in Medium Decomposition into 4 parts:
Our result: HBChPT from Meissner et al., Ann. Phys. 297, 27 (02)
Pion Velocity in Medium Lee et al., NPA 741, 161(04)
Damping of Pions • No Damping in our valid range
We will study… • How to determine our parameters • How to introduce and deal with cutoffs around Fermi surface (go to Fermi liquid!) • How to make it more precise • How to go to higher densities and to check various scenarios