The amount of baryons detected so far at z=0 is only about 20-30% of thatdetected at z=2, or calculated from the standard big-bang nucleosynthesis.This .missing baryon. problem is now one of the most important topics incosmology. Recent simulations predict that most of the baryons in the presentUniverse reside in a warm-hot intergalactic medium with temperatures of10^5 - 10^7 K, associated with clusters of galaxies. In order to probe thiswarm-hot gas, we propose to observe a quasar behind the Virgo cluster withRGS, and measure the resonant absorption line of O VIII Ly alpha at 653.6eV.This provides a unique opportunity to settle the missing baryon problem andto understand the formation of the large-scale cosmological structure.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2003-07-13T08:38:51Z/2003-07-14T14:22:13Z
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 Ryuichi Fujimoto, 2004, 'Search for warm-hot gas associated with the Virgo cluster', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-wzrhlo4
