| Proposal ID | 020467 |
| Title | EMISSION FROM THE MISSING BARYONS IN THE LOCAL GROUP |
| Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0204670101 |
| DOI | https://doi.org/10.5270/esa-p1h43r9 |
| Principal Investigator, PI | Dr JOEL BREGMAN |
| Abstract | The detection of X-ray absorption and emission lines at z = 0 has beeninterpreted as an extensive isothermal Local Group medium with a gaseous massexceeding the baryonic mass of all Local Group galaxies. A large gaseous masshelps to solve the missing baryon problem , a leading cosmological issue.However, the gas mass is highly model dependent, and in an alternative model,the gas lies in a Galactic halo of size 50 kpc and with a gas mass orders ofmagnitude lower. We can discriminate between the Galactic Halo and Local Groupmodels by determining whether most of the diffuse X-ray emission (0.5-1 keV)lies in front or behind a Magellanic Stream cloud at a distance of 50 kpc. Forthe Local Group model, the MS cloud will absorb the emission beyond it, casting an X-ray shadow . |
| Publications |
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| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2004-01-03T05:02:42Z/2004-01-03T19:27:52Z |
| 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. |
| Creator Contact | https://www.cosmos.esa.int/web/xmm-newton/xmm-newton-helpdesk |
| Date Published | 2005-01-30T00:00:00Z |
| Last Update | 2025-01-27 |
| Keywords | "gaseous mass helps", "alternative model", "diffuse xray emission", "missing baryon", "model dependent", "gaseous mass", "kev lies", "galactic halo", "emission lines", "xray absorption", "magellanic stream cloud", "extensive isothermal local", "xray shadow", "missing baryons", "baryonic mass", "magnitude lower", "ms cloud", "leading cosmological issue", "gas mass", "gas lies" |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, Dr JOEL BREGMAN, 2005, 'EMISSION FROM THE MISSING BARYONS IN THE LOCAL GROUP', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-p1h43r9 |