| Proposal ID | 020206 |
| Title | THE NATURE OF SOFT X-RAY WEAK QSOS |
| Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0202060101 |
| DOI | https://doi.org/10.5270/esa-puwijkf |
| Principal Investigator, PI | Dr NORBERT SCHARTEL |
| Abstract | About 10% of the quasars can be classified as soft X-ray-weak, whose X-rayemission is by a factor 10-30 fainter than in typical quasars. They show astrong correlation between Alpha(OX) and the C IV absorption equivalent width,which suggest that absorption is the primary cause of their soft X-ray-weakness. But the shape of the correlation can not be reproduced by an uniformscreen covering both the X-ray source and the ultraviolet emission. Thereforeeither the UV and X-ray absorbers are not identical (warm absorber, partlycovered, only scattered flux) or the X-ray weakness is due to a peculiarproperty of the nuclear emission, as extreme variability or unusual steepness. |
| Publications |
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| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2004-12-31T01:12:42Z/2005-05-08T14:38:50Z |
| 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 | 2006-06-15T00:00:00Z |
| Last Update | 2025-01-27 |
| Keywords | "soft xray weakness", "identical warm absorber", "ultraviolet emission", "xray absorbers", "xray source", "uniform screen", "nuclear emission", "xray weakness", "xray emission", "scattered flux", "typical quasars", "partly covered", "soft xray weak" |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, Dr NORBERT SCHARTEL, 2006, 'THE NATURE OF SOFT X-RAY WEAK QSOS', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-puwijkf |