There is evidence that ultra-compact dwarf galaxies have ^ated mass-to-lightratios, possibly massive black holes (MBHs). Using stellar dynamics (SD) it wasargued that five such UCDs host MBHs in their nuclei ( 10^{6} <M_{\bullet}/M_{\odot} < 10^{7} ). However, robust SD measurements of BH massesare possible in near galaxies, where the BH sphere of influence iswell-resolved. It is thus important to find multiple lines of evidence for thepresence of such BHs. BHs accreting in a hard-state follow a scaling relationbetween their mass, radio, and X-ray luminosity. We selected two UCDs whereevidence for nuclear BHs has been found from SD. We propose to performsimultaneous X and radio observations to assess whether accreting BHs are indeed present in the nuclei of these two galaxies.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-06-08T18:53:28Z/2019-06-09T11:36:48Z
Version
17.56_20190403_1200
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Dr Davide Lena, 2020, 'Do massive BHs really reside in the nuclei of ultra-compact dwarf galaxiesquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-pvb8dul
