A dataset provided by the European Space Agency

Name: Weak Line Quasars at High Redshift: Extremely High Accretion Rate SourcesquestionMark
Published: 2018-01-24T23:00:00Z

Proposal ID	078236
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=0782360101 https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0782360201
DOI	https://doi.org/10.5270/esa-u3q2hrl
Principal Investigator, PI	Prof Ohad Shemmer
Abstract	The broad C IV emission lines in weak line quasars (WLQs) are significantlyweaker than expected from the anti-correlation between C IV equivalent width andthe Hbeta-based Eddington ratio. This discrepancy may be reconciled if theEddington ratios of WLQs are higher than those indicated by Hbeta. We aim totest this hypothesis by measuring the hard-X-ray photon index in all WLQs withHbeta measurements thus obtaining robust determinations of their accretionrates. Steep spectral slopes will indicate that high accretion rates areresponsible for the line weakness in WLQs. Otherwise, additional parameters maycontrol broad emission line equivalent widths. The results will yield crucialinsights about the accretion process and broad emission line formation in all active galactic nuclei.
Publications	Steep Hard-X-Ray Spectra Indicate Extremely High Accretion Rates in Weak Emission-line Quasars \|Marlar, Andrea, Shemmer, Ohad, et al. \| ApJ \| 865-92 \| 2018 \| 2018ApJ...865...92M \| http://ui.adsabs.harvard.edu/#abs/2018ApJ...865...92M Classification of 4XMM-DR9 sources by machine learning \|Zhang, Yanxia, Zhao, Yongheng, \| MNRAS \| 503-5263 \| 2021 \| 2021MNRAS.503.5263Z \| http://ui.adsabs.harvard.edu/#abs/2021MNRAS.503.5263Z X\\u2011HESS: A large sample of highly accreting serendipitous AGN under the XMM\\u2011Newton microscope \|Laurenti, M., Tombesi, F., et al. \| AN \| 344-20230053 \| 2023 \| 2023AN....34430053L \| http://ui.adsabs.harvard.edu/#abs/2023AN....34430053L The XMM-Newton Line Emission Analysis Program (X-LEAP). I. Emission-line Survey of O VII, O VIII, and Fe L-shell Transitions \|Pan, Zeyang, Qu, Zhijie, et al. \| ApJS \| 271-62 \| 2024 \| 2024ApJS..271...62P \| http://ui.adsabs.harvard.edu/#abs/2024ApJS..271...62P From Active Stars to Black Holes: A Discovery Tool for Galactic X-Ray Sources \|Rodriguez, Antonio C., \| PASP \| 136-054201 \| 2024 \| 2024PASP..136e4201R \| http://ui.adsabs.harvard.edu/#abs/2024PASP..136e4201R Robust constraints on feebly interacting particles using XMM-Newton \|Luque, Pedro De la Torre, Balaji, Shyam, \| PhRvD \| 109-L101305 \| 2024 \| 2024PhRvD.109j1305L \| http://ui.adsabs.harvard.edu/#abs/2024PhRvD.109j1305L Multimessenger search for electrophilic feebly interacting particles from supernovae \|Luque, Pedro De la Torre, Balaji, Shyam, \| PhRvD \| 109-103028 \| 2024 \| 2024PhRvD.109j3028L \| http://ui.adsabs.harvard.edu/#abs/2024PhRvD.109j3028L Importance of Cosmic-Ray Propagation on Sub-GeV Dark Matter Constraints \|De la Torre Luque, Pedro, Balaji, Shyam, \| ApJ \| 968-46 \| 2024 \| 2024ApJ...968...46D \| http://ui.adsabs.harvard.edu/#abs/2024ApJ...968...46D
Instrument	EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage	2016-07-19T01:11:35Z/2017-01-04T18:30:53Z
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	2018-01-24T23:00:00Z
Keywords	"eddington ratio", "accretion rates", "hbeta measurements", "line weakness", "anti correlation", "weak line quasars", "spectral slopes", "eddington ratios", "active galactic nuclei", "iv emission lines", "iv equivalent width", "accretion process", "robust determinations", "additional parameters"
Publisher And Registrant	European Space Agency
Credit Guidelines	European Space Agency, Prof Ohad Shemmer, 2018, 'Weak Line Quasars at High Redshift: Extremely High Accretion Rate SourcesquestionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-u3q2hrl