Soft gluon emission from heavy quark scattering in strongly interacting quark-gluon plasma

We apply Low's theorem to soft gluon emission from heavy quark scattering in the nonperturbative strongly interacting quark-gluon plasma (sQGP). The sQGP is described in terms of the dynamical quasiparticles and adjusted to reproduce the EoS from lattice QCD at finite temperature and chemical potential. Since the emitted gluon is soft and of long wavelength, it does not provide information on the detailed structure of the scattering, and only the emission from incoming and outgoing partons is enough. It simplifies the calculations making the scattering amplitude factorizable into the elastic scattering and the emission of soft gluon. Imposing a proper upper limit on the emitted gluon energy, we obtain the gauge-invariant scattering cross sections of heavy quarks with the massive partons of the medium as well as their transport coefficients (momentum drag and diffusion) in the QGP and compare with those from the elastic scattering without gluon emission.