Properties of kaon at non-zero temperature and baryon chemical potential

Abstract

We investigate the spectroscopic properties of the strange particle kaon in the framework of hot and dense QCD. To this end, first, we find the perturbative spectral density, which is connected with both the temperature $T$ and the baryon chemical potential $\mu_{B}$. We include the non-perturbative operators as functions of temperature and baryon chemical potential up to mass dimension five. We perform the calculations in momentum space and use the quark propagator in the hot and dense medium. The numerical results at non-zero temperature and baryon chemical potential demonstrate that the mass of the particle rises considerably by increasing the baryon chemical potential at a fixed temperature (for both the zero and non-zero temperatures) up to approximately $\mu_{B}=0.4$ GeV. After this point, it starts to fall by increasing the baryon chemical potential and it vanishes at $\mu_{B}=(1.03-1.15)$ GeV for finite temperatures: The vanishing point moves to lower baryon chemical potentials by increasing the temperature. At zero temperature, the mass reaches to roughly a fixed value at higher baryon chemical potentials. On the other hand, the decay constant decreases considerably with respect to baryon chemical potential up to roughly $\mu_{B}=0.4$ GeV, but after this point, it starts to increase in terms of the baryon chemical potential at finite temperatures. At $T=0$, the decay constant reaches to a fixed value at higher chemical potentials, as well. It is also seen that the obtained results for the mass and decay constant at $T=\mu_{B}=0$ are in good consistency with the existing experimental data. The observations are consistent with the QCD phase diagram in the $T-\mu_{B}$ plane.Comment: 12 Pages, 8 Figures and 3 Table