| Name | 076074 |
| Title | Weak Line Quasars at High Redshift: Extremely High Accretion Rate Sources? |
| URL | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0760740101 |
| DOI | https://doi.org/10.5270/esa-8viqc0l |
| Author | Prof Ohad Shemmer |
| Description | The Sloan Digital Sky Survey has discovered a remarkable group of virgul100 quasars with extremely weak emission lines in their rest-frame optical-UV spectra. We propose to extend our XMM-Newton observations of such sources and obtain imaging spectroscopy of five quasars of this class with a total exposure time of 102 ks, providing virgul1000 photons per source. This will enable an accurate measurement of the hard-X-ray photon index required for a robust determination of the accretion rate in each source. Steep spectral slopes will indicate that high accretion rates may be responsible for the intrinsic weakness of the optical-UV emission lines. The proposed observations will yield crucial insights about the accretion process and broad emission line formation in all active galactic nuclei. |
| Publication | No observations found associated with the current proposal |
| 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 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 | 2016-11-02T23:00:00Z |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, 2016-11-02T23:00:00Z, 076074, 17.56_20190403_1200. https://doi.org/10.5270/esa-8viqc0l |