Pseudo-scalar mesons at finite temperatures from a Dyson-Schwinger-Bethe-Salpeter approach
1 Bogoliubov Laboratory of Theoretical Physics, 141980, JINR, Dubna, Russia
2 International University Dubna, Dubna, Russia
3 Helmholtz-Zentrum Dresden-Rossendorf, PF 510119, 01314 Dresden, Germany
Published online: 3 April 2019
The truncated Dyson-Schwinger–Bethe-Salpeter equations are employed at non-zero temperature. The truncations refer to a rainbow-ladder approximation augmented with an interaction kernel which facilitates a special temperature dependence. At low temperatures, T → 0, we recover a quark propagator from the Dyson-Schwinger (gap) equation smoothly interpolating to the T = 0 results. Utilizing that quark propagator we evaluate the Bethe-Salpeter vertex function in the pseudo-scalar qq̅ channel for the lowest boson Matsubara frequencies and find a competition of qq̅ bound states and quasi-free two-quark states at T = O (100 MeV).
© The Authors, published by EDP Sciences, 2019