Galaxy groups contain the majority of galaxies, and probably most ofthe baryons, in the Universe. Unfortunately the low X-ray surfacebrightness of groups has prevented the detection of the gas at largeradii which should dominate their baryon content. The superbsensitivity of XMM offers the first opportunity to remedy this. Wepropose, for the first time, to trace the surface brightness ofseveral groups out to their virial radii. This will allow us tomeasure total gas and iron masses, baryon fractions, and mass/light,gas/star and iron-mass/light ratios, and to investigate the
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2001-05-07T11:45:02Z/2001-11-02T22:01:52Z
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 Trevor Ponman, 2003, '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-ew5iczp
