Galaxy groups probably contain most of the baryons in the Universe.Unfortunately the low X-ray surface brightness of groups has prevented thedetection of the gas at large radii which should dominate their baryon content.We propose, for the first time, to trace the surface brightness of a few groupsout to close to R_200. This will allow us to measure total gas and iron masses,baryon fractions, and mass/light, gas/star, and iron-mass/light ratios, and toinvestigate the differences from rich clusters. Coupled with results fromexisting XMM data, this will provide template profiles for extrapolating theproperties of groups to large radii, test formation scenarios for groups, andtest whether clusters can be formed by the merger of galaxy groups.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2004-04-24T13:57:33Z/2004-04-30T16:03:56Z
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, Mr JESPER RASMUSSEN, 2005, 'THE TOTAL BARYON FRACTION IN GROUPS: MAPPING HOT GAS OUT TO THE VIRIAL RADIUS', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-jubp08a
