Pion decay constant and the ρ-meson mass at finite temperature in hidden local symmetry

We study the temperature dependence of the pion decay constant and ρ-meson mass in the hidden local symmetry model at one loop. Using the standard imaginary time formalism, we include the thermal effect of the ρ meson as well as that of the pion. We show that the pion gives a dominant contribution to the pion decay constant and the ρ-meson contribution slightly decreases the critical temperature. The ρ-meson pole mass increases as T4/mρ2 at low temperature, dominated by the pion-loop effect. At high temperature, although the pion-loop effect decreases the ρ-meson mass, the ρ-loop contribution overcomes the pion-loop contribution and the ρ-meson mass increases with temperature. We also show that the conventional parameter a is stable as the temperature increases. copyright 1997 The American Physical Society