A dataset provided by the European Space Agency

Name: Unifying X-ray Weak Quasars: Is there a Highly Absorbed Component in PHL 1811questionMark
Published: 2016-12-12T23:00:00Z

Proposal ID	076191
Title	Unifying X-ray Weak Quasars: Is there a Highly Absorbed Component in PHL 1811?
Download Data Associated to the proposal	https://nxsa.esac.esa.int/nxsa-sl/servlet/data-action-aio?obsno=0761910201
DOI	https://doi.org/10.5270/esa-lggb7q6
Principal Investigator, PI	Prof Karen Leighly
Abstract	Quasars exhibit X-ray emission proportional to their UV emission, and most X-rayweak objects are absorbed. The exception may be PHL 1811, a nearby quasar thatis 25--100 times X-ray fainter than expected, but has a steep and variable X-rayspectrum suggesting a direct view of the central engine. It also has unusual UVemission line properties that are consistent with its X-ray weak SED. Searchesfor PHL 1811 analogs, chosen by their UV spectral properties, find objects thatare X-ray weak but which have hard X-ray spectra, suggesting absorption.Previous X-ray observations of PHL 1811 extended only to 6 keV, so a highlyabsorbed component can.t be ruled out. We propose coordinated XMM- Newton andNuSTAR observations to see whether PHL 1811 is intrinsically normal and highly absorbed.
Publications	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 NuSTAR Observations of Intrinsically X-Ray Weak Quasar Candidates: An Obscuration-only Scenario \|Wang, Chaojun, Luo, B., et al. \| ApJ \| 936-95 \| 2022 \| 2022ApJ...936...95W \| http://ui.adsabs.harvard.edu/#abs/2022ApJ...936...95W 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	2015-11-29T09:38:07Z/2015-11-30T02:08:07Z
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	2016-12-12T23:00:00Z
Keywords	"xray weak sed", "NuSTAR", "nearby quasar", "uv spectral properties", "XMM", "phl 1811", "coordinated xmm newton", "variable xray spectrum", "uv emission", "absorbed component", "hard xray spectra", "phl 1811 analogs", "xray weak objects", "xray fainter", "phl 1811 ?.", "central engine", "xray weak"
Publisher And Registrant	European Space Agency
Credit Guidelines	European Space Agency, Prof Karen Leighly, 2016, 'Unifying X-ray Weak Quasars: Is there a Highly Absorbed Component in PHL 1811questionMark', 17.56_20190403_1200, European Space Agency, https://doi.org/10.5270/esa-lggb7q6