| Name | 014519 |
| Title | Shadowing the Diffuse Extragalactic X-Ray Background |
| URL | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0145190101 |
| DOI | https://doi.org/10.5270/esa-15fmbmf |
| Author | Prof Joel Bregman |
| Description | The majority of the baryons in the present-day universe are "missing" in that they are not in galaxies or as cool intergalactic gas (<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. |
| Publication | No observations found associated with the current proposal |
| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2003-02-20T15:33:39Z/2003-03-01T04:17:31Z |
| Version | 17.56_20190403_1200 |
| Mission Description | 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. |
| Creator Contact | https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk |
| Date Published | 2004-03-16T00:00:00Z |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, 2004-03-16T00:00:00Z, 014519, 17.56_20190403_1200. https://doi.org/10.5270/esa-15fmbmf |