Follow-up Observation of a Hyperluminous Intermediate-mass Black Hole Candidate

Intermediatemass black holes (IMBH, virgul10^210^5 msun) have been long soughtafter because they are associated with several important astrophysicalprocesses. The best IMBH candidates are hyperluminous offnuclear Xray sources(HLXs) with LX>10^41 erg/s, but very few are known. We have identified a new HLXcandidate (LXvirgul10^43 erg/s), at an offset of 11.6 (12 kpc) from the center ofits host galaxy (D_L247 Mpc). We request a deep (60 ks) XMMNewton observationof the source in AO17 to measure its flux and spectral evolution while it is inthe decay phase of a prolonged outburst, in order to demonstrate its IMBH natureand confirm our tidal disruption event explanation for the outburst. An HSTorbit is also requested to confirm that our source is in a star cluster. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]