Spectral properties of acoustic black hole radiation: broadening the horizon

摘要: The sensitivity of the black hole spectrum when introducing short distance dispersion is studied in context atomic Bose condensates. By considering flows characterized by several length scales, we show that, while remains remarkably Planckian, temperature no longer fixed surface gravity. Rather it determined average flow gradient across horizon over an interval healing and gravity, as if was broadened. This valid long does not induce non-adiabatic effects that produce oscillations or some parametric amplification flux.