We define, based on optical galaxy distributions, an unbiased sample of mergingclusters to compile various merger phases. The ROSAT image stacked over cluster-subcluster pairs shows that the X-ray emitting gas in the central region iselongated along the merger axis, however, outside the core it is extended alongits perpendicular direction. It implies that the gas halo is pushed outwardsperpendicular to the merger axis by colliding two gas cores. XMM-Newtonsnapshots of the clusters enable us to identify cluster merger phases andprovide a robust evidence of the gas extended perpendicular to the merger axis,for the first time. Furthermore,we measure X-ray temperature and luminositywithin r500, in order to quantify merger boost by comparing with weak-lensing masses.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2019-08-06T23:49:43Z/2019-08-10T11:02:43Z
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, Prof Nobuhiro Okabe, 2020, 'Detection of Extended Gas Perpendicular to Cluster Merger Axes', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-gutlbsj
