  Using the Damour-Ruffini-Sannan, the Parikh-Wilczek and the thin film
brick-wall models, we investigate the Hawking radiation of uncharged massive
particles from 4-dimensional linear dilaton black holes, which are the
solutions to Einstein-Maxwell-Dilaton, Einstein-Yang-Mills-Dilaton and
Einstein-Yang-Mills-Born-Infeld-Dilaton theories. Our results show that the
tunneling rate is related to the change of Bekenstein-Hawking entropy. Contrary
to the many studies in the literature, here the emission spectrum is precisely
thermal. This implies that the derived emission spectrum is not consistent with
the unitarity of the quantum theory, which would possibly lead to the
information loss.
