Observations of intrahour variable quasars: scattering in our Galactic neighbourhood
Interstellar scintillation (ISS) has been established as the cause of the random variations seen at centimetre wavelengths in many compact radio sources on timescales of a day or less. Observations of ISS can be used to probe structure both in the ionized insterstellar medium of the Galaxy and in...
| Main Authors: | , , , , , |
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| Format: | Journal Article |
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Taylor & Francis
2007
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| Online Access: | http://hdl.handle.net/20.500.11937/39113 |
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| author | Bignall, Hayley Jauncey, D. Lovell, J. Tzioumis, A. Macquart, Jean-Pierre Kedziora-Chudczer, L. |
| author_facet | Bignall, Hayley Jauncey, D. Lovell, J. Tzioumis, A. Macquart, Jean-Pierre Kedziora-Chudczer, L. |
| author_sort | Bignall, Hayley |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Interstellar scintillation (ISS) has been established as the cause of the random variations seen at centimetre wavelengths in many compact radio sources on timescales of a day or less. Observations of ISS can be used to probe structure both in the ionized insterstellar medium of the Galaxy and in the extragalactic sources themselves down to µ as scales. A few quasars have been found to show large amplitude scintillations on unusually rapid, intrahour timescales. This has been shownto be due to weak scattering in very local Galactic ‘screens’, within a few tens of parsec of the Sun. The short variability timescales allowdetailed study of the scintillation properties in relatively short observation periods with compact interferometric arrays. The three best-studied ‘intrahour variable’ quasars, PKS 0405-385, J1819+3845 and PKS 1257-326, have been instrumental in establishing ISS as the principal cause of intraday variability at centimetre wavelengths. Here we review the relevant results from observations of these three sources. |
| first_indexed | 2025-11-14T08:57:20Z |
| format | Journal Article |
| id | curtin-20.500.11937-39113 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:57:20Z |
| publishDate | 2007 |
| publisher | Taylor & Francis |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-391132017-02-28T01:40:39Z Observations of intrahour variable quasars: scattering in our Galactic neighbourhood Bignall, Hayley Jauncey, D. Lovell, J. Tzioumis, A. Macquart, Jean-Pierre Kedziora-Chudczer, L. IDV Quasars Interstellar scintillation Interstellar scintillation (ISS) has been established as the cause of the random variations seen at centimetre wavelengths in many compact radio sources on timescales of a day or less. Observations of ISS can be used to probe structure both in the ionized insterstellar medium of the Galaxy and in the extragalactic sources themselves down to µ as scales. A few quasars have been found to show large amplitude scintillations on unusually rapid, intrahour timescales. This has been shownto be due to weak scattering in very local Galactic ‘screens’, within a few tens of parsec of the Sun. The short variability timescales allowdetailed study of the scintillation properties in relatively short observation periods with compact interferometric arrays. The three best-studied ‘intrahour variable’ quasars, PKS 0405-385, J1819+3845 and PKS 1257-326, have been instrumental in establishing ISS as the principal cause of intraday variability at centimetre wavelengths. Here we review the relevant results from observations of these three sources. 2007 Journal Article http://hdl.handle.net/20.500.11937/39113 Taylor & Francis restricted |
| spellingShingle | IDV Quasars Interstellar scintillation Bignall, Hayley Jauncey, D. Lovell, J. Tzioumis, A. Macquart, Jean-Pierre Kedziora-Chudczer, L. Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title | Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title_full | Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title_fullStr | Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title_full_unstemmed | Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title_short | Observations of intrahour variable quasars: scattering in our Galactic neighbourhood |
| title_sort | observations of intrahour variable quasars: scattering in our galactic neighbourhood |
| topic | IDV Quasars Interstellar scintillation |
| url | http://hdl.handle.net/20.500.11937/39113 |