RT Journal Article T1 Hawking radiation as perceived by different observers: an analytic expression for the effective-temperature function A1 Barbado, L. C. A1 Barceló, Carlos A1 Garay Elizondo, Luis Javier AB Given a field vacuum state in a black hole spacetime, this state can be analysed in terms of how it is perceived (in terms of particle content) by different observers. This can be done by means of the effective-temperature function introduced by Barcelo et al (2011 Phys. Rev. D 83 041501). In Barbado et al (2011 Class. Quantum Grav. 28 125021), this function was analysed in a case-by-case basis for a number of interesting situations. In this work, we find a general analytic expression for the effective-temperature function which, apart from the vacuum state choice, depends on the position, the local velocity and the acceleration of the specific observer. We give a clear physical interpretation of the quantities appearing in the expression, and illustrate its potentiality with a few examples. PB IOP Publishing Ltd SN 0264-9381 YR 2012 FD 2012-04-12 LK https://hdl.handle.net/20.500.14352/44511 UL https://hdl.handle.net/20.500.14352/44511 LA spa NO ©IOP Publishing Ltd.The authors want to thank an anonymous referee for some useful comments and suggestions. Financial support was provided by the Spanish MICINN through the projects FIS2008-06078-C03-01, FIS2008-06078-C03-03, FIS2011-30145-C03-01 and FIS2011-30145-C03-02 (with FEDER contribution), and by the Junta de Andalucía through the project FQM219. NO Spanish MICINN/MINECO NO Junta de Andalucia DS Docta Complutense RD 11 may 2025