Title: Photospheric Emission of Gamma-Ray Bursts,
Abstract: We review the physics of GRB production by relativistic jets that start
highly opaque near the central source and then expand to transparency. We
discuss dissipative and radiative processes in the jet and how radiative
transfer shapes the observed nonthermal spectrum released at the photosphere. A
comparison of recent detailed models with observations gives estimates for
important parameters of GRB jets, such as the Lorentz factor and magnetization.
We also discuss predictions for GRB polarization and neutrino emission.