The observed X-ray luminosities of groups are inconsistent with a model in whichthe intragroup medium is shock-heated during the collapse. It is thought that acombination of pre-heating, gas cooling and energy injection removes low entropygas, reducing the system.s X-ray luminosity. However, the extent of this processis uncertain because the previous selection of group catalogs has been based onX-ray emission. We have constructed a complete, mass-selected catalog of groupsfrom the 2dFGRS. X-ray observations of this sample would for the first timeprovide accurate determinations of the entropy in a mass-selected sample. Theseobservations are of key importance for understanding the thermal history of theintragroup medium and the interplay between X-ray cooling and galaxy formation.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2004-05-20T18:25:36Z/2005-06-18T22:26:50Z
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 PASQUALE MAZZOTTA, 2006, 'X-RAY PROPERTIES OF A MASS-SELECTED GROUP CATALOG', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-a4lnkca
