We consider the response of an Unruh-DeWitt detector near extremal charged black hole, modeling near-horizon region this spacetime by Bertotti-Robinson spacetime. The advantage employing limit is that two-point functions for a massless scalar field are obtainable in closed form number quantum states interest. coupled to both Boulware vacuum state and arbitrary thermal states, including Hartle-H...

A ‘transXend’ detector measures X-rays as electric current and yields an X-ray energy spectrum after analysis. Response functions are necessary for the analysis previously estimated using m...