We propose XMM-Newton observations of two X-ray luminous groups at intermediateredshifts that do not follow the morphological trends found for nearby X-raygroups. In particular, the X-ray emission in these systems is not centered on adominant elliptical galaxy. Such systems are very rare in the nearby universe,suggesting significant evolution in the X-ray group population over the last 5billion years. Groups without a central galaxy may be systems in the process ofcollapsing for the first time. Our deep XMM-Newton observations will allow us totest this idea by searching directly for substructure in the hot gas and lookingfor the departures expected from optical/X-ray scaling relations.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2006-12-04T20:22:22Z/2006-12-05T09:18:29Z
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 John Mulchaey, 2008, 'X-ray Luminous Groups in the Process of Formation', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-t3aukf5
