Properties of X-ray-selected broad absorption-line quasars
Broad absorption-line quasars (commonly termed BALQSOs) contain the most dramatic examples of active galactic nucleus (AGN) driven winds. The high absorbing columns in these winds, ~1024 cm-2, ensure that BALQSOs are generally X-ray faint. This high X-ray absorption means that almost all BALQSOs hav...
| Main Authors: | , , , , , , , , |
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| Format: | Journal Article |
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Oxford University Press
2008
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| Online Access: | http://hdl.handle.net/20.500.11937/15458 |
| _version_ | 1848748898790670336 |
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| author | Blustin, A. Dwelly, T. Page, M. McHardy, I. Seymour, Nick Kennea, J. Loaring, N. Mason, K. Sekiguchi, K. |
| author_facet | Blustin, A. Dwelly, T. Page, M. McHardy, I. Seymour, Nick Kennea, J. Loaring, N. Mason, K. Sekiguchi, K. |
| author_sort | Blustin, A. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Broad absorption-line quasars (commonly termed BALQSOs) contain the most dramatic examples of active galactic nucleus (AGN) driven winds. The high absorbing columns in these winds, ~1024 cm-2, ensure that BALQSOs are generally X-ray faint. This high X-ray absorption means that almost all BALQSOs have been discovered through optical surveys, and so what little we know about their X-ray properties is derived from very bright optically selected sources. A small number of X-ray-selected BALQSOs (XBALQSOs) have, however, recently been found in deep X-ray survey fields. In this paper we investigate the X-ray and rest-frame ultraviolet (UV) properties of five XBALQSOs for which we have obtained XMM-Newton EPIC X-ray spectra and deep optical imaging and spectroscopy. We find that, although the XBALQSOs have an aox steeper by ~0.5 than normal QSOs, their median aox is nevertheless flatter by 0.30 than that of a comparable sample of optically selected BALQSOs (OBALQSOs). We rule out the possibility that the higher X-ray to optical flux ratio is due to intrinsic optical extinction. We find that the amount of X-ray and UV absorption due to the wind in XBALQSOs is similar, or perhaps greater than, the corresponding wind absorption in OBALQSOs, so the flatter aox cannot be a result of weaker wind absorption. We conclude that these XBALQSOs have intrinsically higher X-ray to optical flux ratios than the OBALQSO sample with which we compare them. © 2008 The Authors. |
| first_indexed | 2025-11-14T07:12:22Z |
| format | Journal Article |
| id | curtin-20.500.11937-15458 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T07:12:22Z |
| publishDate | 2008 |
| publisher | Oxford University Press |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-154582017-09-13T13:41:02Z Properties of X-ray-selected broad absorption-line quasars Blustin, A. Dwelly, T. Page, M. McHardy, I. Seymour, Nick Kennea, J. Loaring, N. Mason, K. Sekiguchi, K. Broad absorption-line quasars (commonly termed BALQSOs) contain the most dramatic examples of active galactic nucleus (AGN) driven winds. The high absorbing columns in these winds, ~1024 cm-2, ensure that BALQSOs are generally X-ray faint. This high X-ray absorption means that almost all BALQSOs have been discovered through optical surveys, and so what little we know about their X-ray properties is derived from very bright optically selected sources. A small number of X-ray-selected BALQSOs (XBALQSOs) have, however, recently been found in deep X-ray survey fields. In this paper we investigate the X-ray and rest-frame ultraviolet (UV) properties of five XBALQSOs for which we have obtained XMM-Newton EPIC X-ray spectra and deep optical imaging and spectroscopy. We find that, although the XBALQSOs have an aox steeper by ~0.5 than normal QSOs, their median aox is nevertheless flatter by 0.30 than that of a comparable sample of optically selected BALQSOs (OBALQSOs). We rule out the possibility that the higher X-ray to optical flux ratio is due to intrinsic optical extinction. We find that the amount of X-ray and UV absorption due to the wind in XBALQSOs is similar, or perhaps greater than, the corresponding wind absorption in OBALQSOs, so the flatter aox cannot be a result of weaker wind absorption. We conclude that these XBALQSOs have intrinsically higher X-ray to optical flux ratios than the OBALQSO sample with which we compare them. © 2008 The Authors. 2008 Journal Article http://hdl.handle.net/20.500.11937/15458 10.1111/j.1365-2966.2008.13825.x Oxford University Press unknown |
| spellingShingle | Blustin, A. Dwelly, T. Page, M. McHardy, I. Seymour, Nick Kennea, J. Loaring, N. Mason, K. Sekiguchi, K. Properties of X-ray-selected broad absorption-line quasars |
| title | Properties of X-ray-selected broad absorption-line quasars |
| title_full | Properties of X-ray-selected broad absorption-line quasars |
| title_fullStr | Properties of X-ray-selected broad absorption-line quasars |
| title_full_unstemmed | Properties of X-ray-selected broad absorption-line quasars |
| title_short | Properties of X-ray-selected broad absorption-line quasars |
| title_sort | properties of x-ray-selected broad absorption-line quasars |
| url | http://hdl.handle.net/20.500.11937/15458 |