Spectral Density of (Pseudo)Scalar Currents at Finite Temperature

TL;DR

This paper investigates the spectral densities of (pseudo)scalar currents at finite temperature with unequal quark masses, revealing an additional branch cut due to medium absorption effects, consistent with vacuum results at zero temperature.

Contribution

It introduces the finite-temperature spectral density calculation for (pseudo)scalar currents with different quark masses, highlighting the emergence of a new branch cut from medium interactions.

Findings

Additional branch cut in spectral density due to medium absorption

Results agree with vacuum case as temperature approaches zero

Provides a basis for phenomenological hadronic parameter studies

Abstract

We study the spectral densities of (pseudo)scalar currents at finite temperature in general case when mass of two quarks are different. Such spectral densities are necessary for the phenomenological investigation of hadronic parameters. We use quark propagator at finite temperature and show that an additional branch cut arises in spectral density, which corresponds to particle absorption from the medium. The obtained results at T \rightarrow 0 limit are in good agreement with the vacuum results.