Galaxy cluster outskirts are the regions where structure formation occursthrough the accretion of smaller structures along large-scale filaments.Recently, it has been claimed both from observations and numerical simulationsthat an important fraction of the infalling material should be in the form ofdense clumps. If this is the case, we argue that a sufficiently long XMMobservation should allow us to detect these clumps and distinguish them frompoint sources. We propose 8 25 ks observations of the outskirts of Hydra A andA2142, which were selected based on their high azimuthal scatter in ROSATobservations. The proposed program will allow us to set constraints on theexistence of dense clumps down to a flux of 2e-15 ergs cm-2 s-1 (0.5-2.0 keV band) and a scale of 10-80 kpc.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2012-05-13T08:49:33Z/2012-07-18T11:24:13Z
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 Dominique Eckert, 2013, 'Gas clumping in the outskirts of Hydra A and A2142', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-252oev7
