Low-energy sector quantization of a massless scalar field outside a Reissner-Nordstrom black hole and static sources - art. no. 064001

We quantize the low-energy sector of a massless scalar field in Reissner-No rdstrom spacetime. This allows the analysis of processes involving soft sca lar particles occurring outside charged black holes. In particular, we comp ute the response of a static scalar source interacting with Hawking radiati on using the Unruh (and the Hartle-Hawking) vacuum. This response is compar ed with the one obtained when the source is uniformly accelerated in the us ual vacuum of Minkowski spacetime with the same proper acceleration. We sho w that both responses are in general different in opposition to the result obtained when the Reissner-Nordstrom black hole is replaced by a Schwarzsch ild one. The conceptual relevance of this result is commented on.