Masses of vector bosons in two-color dense QCD based on the hidden local symmetry

TL;DR

This paper develops a low-energy effective theory for two-color QCD including vector bosons and studies how their masses depend on baryon density, revealing phase transitions and mixing effects among mesons and baryons.

Contribution

It introduces a novel effective Lagrangian incorporating vector bosons in two-color QCD based on hidden local symmetry, analyzing their mass behavior at finite density.

Findings

Vector boson masses depend on baryon density .

Mass differences relate to mixing between diquark baryons and anti-baryons.

Phase transition indicated by -dependence of vector boson masses.

Abstract

We construct a low energy effective Lagrangian for the two-color QCD including the "vector" bosons (mesons with J^P=1^- and diquark baryons with J^P=1^+) in addition to the pseudo Nambu-Goldstone bosons with a degenerate mass M_\pi (mesons with J^P=0^- and baryons with J^P=0^+) based on the chiral symmetry breaking pattern of SU(2N_f) \to Sp(2N_f) in the framework of the hidden local symmetry. We investigate the dependence of the "vector" boson masses on the baryon number density \mu_B. We show that the \mu_B-dependence signals the phase transition of U(1)_B breaking. We find that it gives information about mixing among "vector" bosons: e.g. the mass difference between \rho and \omega mesons is proportional to the mixing strength between the diquark baryon with J^P=1^+ and the anti-baryon. We discuss the comparison with lattice data for two-color QCD at finite density.