Hawking radiation from covariant anomalies in (2+1)-dimensional black holes

In an insightful approach, Robinson and Wilczek proposed that Hawking radiation can be obtained as the compensation of a breakdown of general covariance and gauge invariance and the radiation is a black body radiation at Hawking temperature. We apply this method to two types of black holes in three-dimensional spacetime, both of which have the form of a metric such that the tt component of the metric is not inverse of the rr component of the metric. The first one is the warped AdS(3) black hole in three-dimensional topologically massive gravity with the negative cosmological constant, and the second one is the charged rotating black hole in three dimensions.