Vector-axialvector mixing from a chiral effective field theory at finite temperature

Harada, M.; Sasaki, C.; Weise, W.

Vector-axialvector mixing from a chiral effective field theory at finite temperature

Authors

Harada, M.

Sasaki, C.

Weise, W.

Description

We study the vector-axialvector mixing in a hot medium and its evolution toward the chiral phase transition using different symmetry restoration scenarios based on the generalized hidden local symmetry framework. We show that the presence of the $a_1$ meson reduces the vector spectral function around $ρ$ meson mass and enhances it around $a_1$ meson mass. The coupling strength of $a_1$ to $ρ$ and $π$ vanishes at the critical temperature due to the degenerate $ρ$-$a_1$ masses. This feature holds rigorously in the chiral limit and still stays intact to good approximation for the physical pion mass.
v2:11 pages, 6 figures, reorganized and expanded the text, new plots and references added, main result and conclusions unchanged