| Proposal ID | 090220 |
| Title | Comparison of X-ray and Optical/UV Eddington Ratio Estimates in Quasars |
| Download Data Associated to the proposal | https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0902200301 |
| DOI | https://doi.org/10.57780/esa-fcsoiil |
| Principal Investigator, PI | Dr Gordon Richards |
| Abstract | We request 190 ks on a uniform sample of 12 optically-selected, low-z,radio-quiet SDSS quasars. The range of L/LEdd complement the ~60 well-studied,but potentially biased (in terms of L/LEdd) reverberation mapped (RM)quasars. With both SDSS and HST spectroscopy, we are able to estimate L/Leddfrom 3 optical/UV-based estimators. X-ray data from Chandra enables a 4thL/LEdd estimator (alpha_ox) for the full sample of 25 objects. The 12 proposedtargets lack sufficient Chandra counts to investigate the robustness of the hardX-ray spectral index, Gamma, as an indicator of L/LEdd. Our observations willenable intercomparison of 5 optical/UV and X-ray estimators of L/LEdd for awell-defined sample of quasars. |
| Publications | No publications found for current proposal! |
| Instrument | EMOS1, EMOS2, EPN, OM, RGS1, RGS2 |
| Temporal Coverage | 2022-11-27T14:27:32Z/2022-11-27T19:55:52Z |
| Version | 20.09_20221024_1724 |
| 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 | 2023-12-30T00:00:00Z |
| Last Update | 2025-01-27 |
| Keywords | "ledd estimator alpha_ox", "uniform sample", "xray data", "SDSS", "uv eddington ratio", "hst spectroscopy", "ledd complement", "xray estimators", "potentially biased", "low z", "defined sample", "chandra counts", "HST" |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, Dr Gordon Richards, 2023, 'Comparison of X-ray and Optical/UV Eddington Ratio Estimates in Quasars', 20.09_20221024_1724, European Space Agency, https://doi.org/10.57780/esa-fcsoiil |