The breaking of self-similarity in virialised systems occurs in the mass regime least amenable to global study of its hot gas, due to the low surface brightness of X-ray halos in small systems. Inability to determine the virial radius with certainty undermines attempts to study the scaling properties of systems across a wide range of masses. XMM offers the first opportunity to resolve this issue, with a direct determination of the virial radius in 2keV clusters, which are cool enough to be strongly affected by non-gravitational processes, but bright enough to provide good statistics. These observations will permit us to map the gas properties out to large radii and hence establish whether trends reported in the M:T relation and the gas fraction are real or spurious.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2002-12-21T21:58:15Z/2002-12-22T12:57:36Z
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, Prof Trevor Ponman, 2004, 'The Virial Radius of 2 keV Clusters', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-fhatccg
