Vector mesons spectrum in a medium with a chiral imbalance induced by the vacuum of fermions

TL;DR

This paper investigates how a chiral imbalance in a medium affects the mass spectrum of light vector mesons, revealing additional radiative contributions that influence meson polarization splitting.

Contribution

It introduces a novel analysis of vector meson spectra considering chiral imbalance and identifies new radiative effects beyond the Chern-Simons term.

Findings

Mass spectrum depends on momentum and chiral chemical potential.

Additional radiative contributions affect polarization splitting.

Effects become significant at a few hundred MeV.

Abstract

The properties of the light vector mesons in the presence of local parity breaking medium with a chiral imbalance are considered in the vector-meson dominance model. Applying the finite lowest-order radiatively induced local effective Lagrangian, initially developed for the QED, for the vector $\rho$ and $\omega$ mesons, we obtained the mass spectrum as a function of momentum and chiral chemical potential $\mu_5$. We showed that in addition to the Chern-Simons term, splitting the transverse polarisations of the mesons, there is another radiatively induced contribution that becomes important at momentum and $\mu_5$ around a few hundred MeV.