Confirming spectral state transitions in ESO 243-49 HLX-1

Swift monitoring of the intermediate mass black hole candidate ESO 243-49 HLX-1 found that in August 2009 it dropped in flux by an order of magnitude in conjunction with a possible spectral hardening. The limited throughput of the Swift XRT prevents us from confirming that HLX-1 undergoes transitions between the same canonical spectral states as Galactic black hole binaries. Having performed XMM observations in the high/soft state, we wish to obtain a high quality X-ray spectrum in the low state to confirm the hardening suggested by the XRT. This is the missing piece before conclusions can be drawn from the comparison of its spectral properties with those of Galactic black hole systems.