X-ray measurements of a Ca-rich gap transient

We present Chandra measurements of a calcium-rich gap transient. These objects have properties that would be well-explained by tidal detonation of He white dwarfs, something which can be done by intermediate-mass black holes, but not by supermassive black holes. Previous groups’ theoretical calculations have suggested that tidal detonations lead to substantial amounts of returning material, which is then accreted by the black hole. Our X-ray upper limits on the flux from SN 2012hn show that it is unlikely to be a tidal detonation by an intermediate mass black hole unless the black hole is at the low end of the IMBH mass distribution. We discuss the possibility that the detonation was instead due to a three-body interaction involving a stellar mass black hole.