Studies of galaxy clusters are important for both cosmology and the formation ofbaryonic structures. An important relation in cluster science is the f_gas - Mrelation. However, the cluster samples used to constrain this relation are X-rayselected and the current XMM and Chandra archives are also heavily biased toX-ray selected clusters. To address this important bias, we construct a sampleof 18 most massive clusters from the SDSS-C4 cluster catalog. Nine of them havebeen observed by XMM or Chandra but they are all X-ray luminous, while eight ofthe other nine unobserved clusters are X-ray faint. We propose to observe thesenine unobserved clusters to complete this unique sample, with potentiallyimportant implications on the cluster mass - proxy relations.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2010-07-29T02:22:25Z/2011-04-23T14:47:00Z
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 Ming Sun, 2012, 'Are massive clusters always X-ray luminousquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-w4515dj
