Hadrons at Finite Temperature

Abstract

High energy laboratories are performing experiments in heavy ion collisions to explore the structure of matter at high temperature and density. This elementary book explains the basic ideas involved in the theoretical analysis of these experimental data. It first develops two topics needed for this purpose, namely hadron interactions and thermal field theory. Chiral perturbation theory is developed to describe hadron interactions and thermal field theory is formulated in the real-time method. In particular, spectral form of thermal propagators is derived for fields of arbitrary spin and used to calculate loop integrals. These developments are then applied to find quark condensate and hadron parameters in medium, including dilepton production. Finally, the non-equilibrium method of statistical field theory to calculate transport coefficients is reviewed. With technical details explained in the text and appendices, this book should be accessible to researchers as well as graduate students interested in thermal field theory.

Effect of the anomalous magnetic moment of quarks on the phase structure and mesonic properties in the NJL model

“…To include the effect of finite temperature and density in the mesonic excitations, we use the Real Time Formalism (RTF) of Thermal Field Theory (TFT) [79,80] in which all the two point correlation functions become 2 × 2 matrices in thermal space. However, these matrices can be put in diagonal forms in terms of analytic functions (will be denoted by bars) and thus the knowledge of any one components (say the 11 component) of these matrices are sufficient to know the complete one.…”

General structure of the neutral ρ meson self-energy and its spectral properties in a hot and dense magnetized medium

“…In order to calculate the ρ 0 self energy at finite temperature and density, we employ the real time formalism (RTF) of finite temperature field theory where all the two point correlation functions such as the propagator and the self energy become 2 × 2 matrices in the thermal space [34,35]. However, they can be put in a diagonal form where the diagonal elements can be obtained from any one component (say the 11-component) of the said 2 × 2 matrix.…”

“…The analytic thermal self energy function of ρ 0 denoted by a bar ReΠ µν (q 0 , q) = ReΠ µν π (q 0 , q)+ReΠ µν N (q 0 , q) is related to the above quantities by the relations [35] ReΠ µν π,N (q 0 , q) = ReΠ µν π,N 11…”

Medium effects on the electrical conductivity of a hot pion gas

“…However they can be diagonalized in terms of analytic functions. Following standard prescription [53,54], we obtain the real and imaginary parts of the in-medium self energy functions and they can be written as,…”