| Description: | M82 X-1 is an ultra-luminous X-ray source, that is likely powered by an intermediate mass black hole (IMBH, see pic. from yesterday). We observed the central region of M82 with the EVN at 1 Gbps to look for a radio counterpart to M82 X-1. There is only one source detected in the CHANDRA error box of the source (shown above). This is likely a hot spot in a sunpernova remnant, and is unrelated to the ULX. From this non-detection, we derive a rough upper limit to the black hole mass of about 500 solar masses. Thus, M82 X-1 is either a less massive IMBH, or a stellar mass source with very strong beaming of X-rays in the close vicinity of the black hole. |
