Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-10-06
Mon.Not.Roy.Astron.Soc. 365 (2006) 191-198
Astronomy and Astrophysics
Astrophysics
8 pages, 6 figures, accepted for publication in MNRAS
Scientific paper
We present results from a 112 ks long look by XMM-Newton at the ultraluminous X-ray source (ULX) Holmberg II X-1, long thought to be the one of best candidates for the missing class of intermediate mass black holes (IMBHs). Our data comprises the first high quality XMM-Newton/RGS spectrum of an ULX, and an XMM-Newton/EPIC spectrum with unprecedented signal-to-noise. A detailed timing analysis shows that any variability on time-scales of minutes to hours is very weak (< few per cent fractional rms), though larger amplitude variations on much shorter time-scales could be hidden by photon counting statistics. This result suggests that if Ho II X-1 harbours an IMBH, then we are observing this source in a highly unusual and atypical state when compared with the known variability behaviour of other accreting systems of large mass. Moreover unlike Galactic X-ray binaries, our spectral analysis indicates the possible presence of an optically-thick low temperature corona. Taken together our timing and spectral analysis suggests that the compact companion is most-likely a high luminosity analogue of black hole binary systems similar to GRS 1915+105, the Galactic microquasar, harbouring a compact object of mass no greater than 100 solar masses.
Goad Michael R.
Reeves James N.
Roberts Timothy P.
Uttley Phil
No associations
LandOfFree
A deep XMM-Newton observation of the ultraluminous X-ray source HoII X-1 : the case against a 1000 solar mass black hole does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A deep XMM-Newton observation of the ultraluminous X-ray source HoII X-1 : the case against a 1000 solar mass black hole, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A deep XMM-Newton observation of the ultraluminous X-ray source HoII X-1 : the case against a 1000 solar mass black hole will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-323673