Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309
Since the launch of the Einstein X-ray Observatory in the 1970s, a number of broad absorption features have been reported in the X-ray spectra of BL Lac objects. These features are often interpreted as arising from high-velocity outflows intrinsic to the BL Lac object, therefore providing important...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | en_US |
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IOP Publishing
2012
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| Online Access: | http://hdl.handle.net/1721.1/72091 https://orcid.org/0000-0002-5769-8441 |
| _version_ | 1811074444268929024 |
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| author | Fang, Taotao Buote, David A. Humphrey, Philip J. Canizares, Claude R. |
| author2 | Massachusetts Institute of Technology. Department of Physics |
| author_facet | Massachusetts Institute of Technology. Department of Physics Fang, Taotao Buote, David A. Humphrey, Philip J. Canizares, Claude R. |
| author_sort | Fang, Taotao |
| collection | MIT |
| description | Since the launch of the Einstein X-ray Observatory in the 1970s, a number of broad absorption features have been reported in the X-ray spectra of BL Lac objects. These features are often interpreted as arising from high-velocity outflows intrinsic to the BL Lac object, therefore providing important information about the inner environment around the central engine. However, such absorption features have not been observed more recently with high-resolution X-ray telescopes such as Chandra and XMM-Newton. In this paper, we report the detection of a transient X-ray absorption feature intrinsic to the BL Lac object H 2356-309 with the Chandra X-ray Telescope. This BL Lac object was observed during XMM-Newton cycle 7 and Chandra cycles 8 and 10, as part of our campaign to investigate X-ray absorption produced by the warm-hot intergalactic medium residing in the foreground large-scale superstructure. During one of the 80 ks Chandra cycle 10 observations, a transient absorption feature was detected at 3.3σ (or 99.9% confidence level, accounting for the number of "trials"), which we identify as the O VIII Kα line produced by an absorber intrinsic to the BL Lac object. None of the other 11 observations showed this line. We constrain the ionization parameter (25 lsim Ξ lsim 40) and temperature (105 K <T < 2.5 × 107 K) of the absorber. This absorber is likely produced by an outflow with a velocity up to 1500 km s–1. There is a suggestion of possible excess emission on the long-wavelength side of the absorption line; however, the derived properties of the emission material are very different from those of the absorption material, implying it is unlikely a typical P Cygni-type profile. |
| first_indexed | 2024-09-23T09:49:31Z |
| format | Article |
| id | mit-1721.1/72091 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T09:49:31Z |
| publishDate | 2012 |
| publisher | IOP Publishing |
| record_format | dspace |
| spelling | mit-1721.1/720912022-09-26T13:57:19Z Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 Fang, Taotao Buote, David A. Humphrey, Philip J. Canizares, Claude R. Massachusetts Institute of Technology. Department of Physics Canizares, Claude R. Canizares, Claude R. Since the launch of the Einstein X-ray Observatory in the 1970s, a number of broad absorption features have been reported in the X-ray spectra of BL Lac objects. These features are often interpreted as arising from high-velocity outflows intrinsic to the BL Lac object, therefore providing important information about the inner environment around the central engine. However, such absorption features have not been observed more recently with high-resolution X-ray telescopes such as Chandra and XMM-Newton. In this paper, we report the detection of a transient X-ray absorption feature intrinsic to the BL Lac object H 2356-309 with the Chandra X-ray Telescope. This BL Lac object was observed during XMM-Newton cycle 7 and Chandra cycles 8 and 10, as part of our campaign to investigate X-ray absorption produced by the warm-hot intergalactic medium residing in the foreground large-scale superstructure. During one of the 80 ks Chandra cycle 10 observations, a transient absorption feature was detected at 3.3σ (or 99.9% confidence level, accounting for the number of "trials"), which we identify as the O VIII Kα line produced by an absorber intrinsic to the BL Lac object. None of the other 11 observations showed this line. We constrain the ionization parameter (25 lsim Ξ lsim 40) and temperature (105 K <T < 2.5 × 107 K) of the absorber. This absorber is likely produced by an outflow with a velocity up to 1500 km s–1. There is a suggestion of possible excess emission on the long-wavelength side of the absorption line; however, the derived properties of the emission material are very different from those of the absorption material, implying it is unlikely a typical P Cygni-type profile. United States. National Aeronautics and Space Administration Smithsonian Astrophysical Observatory (contract SV1-61010) 2012-08-10T13:32:14Z 2012-08-10T13:32:14Z 2011-03 2011-02 Article http://purl.org/eprint/type/JournalArticle 0004-637X 1538-4357 http://hdl.handle.net/1721.1/72091 Fang, Taotao et al. “DETECTION OF A TRANSIENT X-RAY ABSORPTION LINE INTRINSIC TO THE BL LACERTAE OBJECT H 2356-309.” The Astrophysical Journal 731.1 (2011): 46. https://orcid.org/0000-0002-5769-8441 en_US http://dx.doi.org/10.1088/0004-637x/731/1/46 Astrophysical Journal Creative Commons Attribution-Noncommercial-Share Alike 3.0 http://creativecommons.org/licenses/by-nc-sa/3.0/ application/pdf IOP Publishing Prof. Canizares via Mat Willmott |
| spellingShingle | Fang, Taotao Buote, David A. Humphrey, Philip J. Canizares, Claude R. Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title | Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title_full | Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title_fullStr | Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title_full_unstemmed | Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title_short | Detection of a Transient X-ray Absorption Line Intrinsic to the Bl Lacertae Object H 2356-309 |
| title_sort | detection of a transient x ray absorption line intrinsic to the bl lacertae object h 2356 309 |
| url | http://hdl.handle.net/1721.1/72091 https://orcid.org/0000-0002-5769-8441 |
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