Vector mesons and dense skyrmion matter

摘要

In our continuing effort to understand hadronic matter at high density, we have developed a unified field theoretic formalism for dense skyrmion matter using a single Lagrangian to describe simultaneously both matter and meson fluctuations and studied in-medium properties of hadrons. Dropping the quartic Skyrme term, we incorporate into our previous Lagrangian the vector mesons rho and omega in a form which is consistent with the symmetries of QCD. The results that we have obtained, reported here, expose a hitherto unsuspected puzzle associated with the role the omega meson plays at short distance. Since the omega meson couples to baryon density, it leads to a pseudo-gap scenario for the chiral symmetry phase transition, which is at variance with standard scenario of QCD at the phase transition. We find that in the presence of the omega mesons, the scale-anomaly dilaton field is prevented from developing a vanishing vacuum expectation value at the chiral restoration, as a consequence of which the in-medium pion decay constant does not vanish. This seems to indicate that the omega degree of freedom obstructs the "vector manifestation" which is considered to be a generic feature of effective field theories matched to QCD. (C) 2004 Published by Elsevier B.V.