| Proposal ID | 076074 |
| Title | Weak Line Quasars at High Redshift: Extremely High Accretion Rate Sources? |
| Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0760740101 |
| DOI | https://doi.org/10.5270/esa-8viqc0l |
| Principal Investigator, PI | Prof Ohad Shemmer |
| Abstract | The Sloan Digital Sky Survey has discovered a remarkable group of ~100 quasarswith extremely weak emission lines in their rest-frame optical-UV spectra. Wepropose to extend our XMM-Newton observations of such sources and obtain imagingspectroscopy of five quasars of this class with a total exposure time of 102 ks,providing ~1000 photons per source. This will enable an accurate measurement ofthe hard-X-ray photon index required for a robust determination of the accretionrate in each source. Steep spectral slopes will indicate that high accretionrates may be responsible for the intrinsic weakness of the optical-UV emissionlines. The proposed observations will yield crucial insights about the accretionprocess and broad emission line formation in all active galactic nuclei. |
| Publications |
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| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2015-06-10T07:53:36Z/2015-10-15T20:25:52Z |
| 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 | 2016-11-02T23:00:00Z |
| Last Update | 2025-01-27 |
| Keywords | "weak emission lines", "accretion rate", "accretion process", "weak line quasars", "xmm newton", "XMM-Newton", "total exposure time", "accretion rates", "XMM", "optiuv emission lines", "imaging spectroscopy", "spectral slopes", "active galactic nuclei" |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, Prof Ohad Shemmer, 2016, 'Weak Line Quasars at High Redshift: Extremely High Accretion Rate Sources?', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-8viqc0l |