In-medium kinetic theory of D mesons and heavy-flavor transport coefficients

Recent progress on in-medium properties of heavy mesons from finite-temperature EFTs

“…It is based on unitarized heavy-meson chiral perturbation theory (HMChPT) combined with thermal field theory techniques using the imaginary-time formalism to address the thermal effects on the properties of heavy mesons in a mesonic medium at finite temperature. The kinetic theory describing the heavy-meson dynamics in the hot medium can be derived using the real-time formalism [39]. The resulting kinetic equation depends on thermal scattering amplitudes and spectral functions.…”

“…In Ref. [39] we calculated the transport coefficients of D mesons in the hadronic phase incorporating medium corrections to the scattering amplitudes. To do so, we extended the kinetic theory of D mesons using the more general Kadanoff-Baym equations, so as to account for thermal and off-shell effects.…”

“…Let us summarize our main results. For a detailed derivation, we recommend to consult our previous work [39] and references therein. Starting from the Kadanoff-Baym equations and performing a Wigner transform along with a gradient expansion [55], we arrive to the following form of the off-shell transport equation for the time ordered Green's function of the heavy meson G < H (X, k),…”

“…In this work we use thermal EFTs to access the finitetemperature properties of charm and bottom mesons in a hot medium. To this end, we will revisit the calculations that we presented in a series of works on charmed mesons [37][38][39][40] and, in addition, we will present extensions of the calculations to the heavy mesons with bottom flavor [40]. We note that, although it will not be discussed here, our findings in the charm sector have been checked against lattice QCD calculations at the level of Euclidean correlators [41] and that we have also studied the thermal modification of the X(3872) exotic state and its spin-flavor partners when these are assumed to be of molecular nature [42].…”

“…In Section 2 we discuss the main ingredients of our thermal EFT approach to address the in-medium properties of open heavy-flavor mesons: The effective hadron-hadron interactions, the use of the imaginarytime formalism to evaluate properties of a system in thermal equilibrium (e.g., thermal corrections to the mass and decay width), and the evolution in real-time to tackle the description of a system out of equilibrium and compute transport coefficients. We will review the key ideas and refer to our previous works for technical details [37][38][39]. Section 3 presents novel results for bottomed mesons.…”