|Shadowing the Diffuse Extragalactic X-Ray Background
|Prof Joel Bregman
|The majority of the baryons in the present-day universe are missing in that they are not in galaxies or as cool intergalactic gas (&amp;lt;1E5K). These baryons are most likely diffuse gas at 1E6 - 1E7 K in regions of modest overdensity, and the superposition of many such regions can produce detectable X-ray emission that accounts for about 10-30% of the X-ray background in the 0.2-1 keV range. To detect this emission, we used the shadowing properties of the gas in the edge-on galaxy NGC 891, and we find a shadow at the 99% confidence level, consistent with a fraction of the XRB in a diffuse cosmic component. We propose additional observations of a better edge-on system, NGC 5907, to determine whether shadows are universal and to better measure the level of this cosmic diffuse XRB.
|No observations found associated with the current proposal
|EMOS1, EMOS2, EPN, OM, RGS1, RGS2
|The European Space Agency's (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESA's 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 Earth's 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.
|Publisher And Registrant
|European Space Agency
|European Space Agency, 2004, 014519, 17.56_20190403_1200. https://doi.org/10.5270/esa-15fmbmf