An automated archival Very Large Array transients survey
In this paper we present the results of a survey for radio transients using data obtained from the Very Large Array archive. We have reduced, using a pipeline procedure, 5037 observations of the most common pointings - i.e. the calibrator fields. These fields typically contain a relatively bright po...
| Main Authors: | , , , , , , , , , , , |
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| Format: | Journal Article |
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Wiley-Blackwell Publishing Ltd.
2011
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| Online Access: | http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2011.18631.x/abstract http://hdl.handle.net/20.500.11937/4477 |
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| author | Bell, M. Fender, R. Swinbank, J. Miller-Jones, James Law, C. Scheers, B. Spreeuw, H. Wise, M. Stappers, B. Wijers, R. Hessels, J. Masters, J. |
| author_facet | Bell, M. Fender, R. Swinbank, J. Miller-Jones, James Law, C. Scheers, B. Spreeuw, H. Wise, M. Stappers, B. Wijers, R. Hessels, J. Masters, J. |
| author_sort | Bell, M. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | In this paper we present the results of a survey for radio transients using data obtained from the Very Large Array archive. We have reduced, using a pipeline procedure, 5037 observations of the most common pointings - i.e. the calibrator fields. These fields typically contain a relatively bright point source and are used to calibrate `target' observations: they are therefore rarely imaged themselves. The observations used span a time range ~ 1984 - 2008 and consist of eight different pointings, three different frequencies (8.4, 4.8 and 1.4 GHz) and have a total observing time of 435 hours. We have searched for transient and variable radio sources within these observations using components from the prototype LOFAR transient detection system. In this paper we present the methodology for reducing large volumes of Very Large Array data; and we also present a brief overview of the prototype LOFAR transient detection algorithms. No radio transients were detected in this survey, therefore we place an upper limit on the snapshot rate of GHz frequency transients > 8.0 mJy to rho less than or equal to 0.032 deg^-2 that have typical timescales 4.3 to 45.3 days. We compare and contrast our upper limit with the snapshot rates - derived from either detections or non-detections of transient and variable radio sources - reported in the literature. When compared with the current Log N - Log S distribution formed from previous surveys, we show that our upper limit is consistent with the observed population. Current and future radio transient surveys will hopefully further constrain these statistics, and potentially discover dominant transient source populations. In this paper we also briefly explore the current transient commissioning observations with LOFAR, and the impact they will make on the field. |
| first_indexed | 2025-11-14T06:02:52Z |
| format | Journal Article |
| id | curtin-20.500.11937-4477 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T06:02:52Z |
| publishDate | 2011 |
| publisher | Wiley-Blackwell Publishing Ltd. |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-44772019-02-19T04:27:18Z An automated archival Very Large Array transients survey Bell, M. Fender, R. Swinbank, J. Miller-Jones, James Law, C. Scheers, B. Spreeuw, H. Wise, M. Stappers, B. Wijers, R. Hessels, J. Masters, J. radio continuum: general astronomical data bases: miscellaneous In this paper we present the results of a survey for radio transients using data obtained from the Very Large Array archive. We have reduced, using a pipeline procedure, 5037 observations of the most common pointings - i.e. the calibrator fields. These fields typically contain a relatively bright point source and are used to calibrate `target' observations: they are therefore rarely imaged themselves. The observations used span a time range ~ 1984 - 2008 and consist of eight different pointings, three different frequencies (8.4, 4.8 and 1.4 GHz) and have a total observing time of 435 hours. We have searched for transient and variable radio sources within these observations using components from the prototype LOFAR transient detection system. In this paper we present the methodology for reducing large volumes of Very Large Array data; and we also present a brief overview of the prototype LOFAR transient detection algorithms. No radio transients were detected in this survey, therefore we place an upper limit on the snapshot rate of GHz frequency transients > 8.0 mJy to rho less than or equal to 0.032 deg^-2 that have typical timescales 4.3 to 45.3 days. We compare and contrast our upper limit with the snapshot rates - derived from either detections or non-detections of transient and variable radio sources - reported in the literature. When compared with the current Log N - Log S distribution formed from previous surveys, we show that our upper limit is consistent with the observed population. Current and future radio transient surveys will hopefully further constrain these statistics, and potentially discover dominant transient source populations. In this paper we also briefly explore the current transient commissioning observations with LOFAR, and the impact they will make on the field. 2011 Journal Article http://hdl.handle.net/20.500.11937/4477 http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2011.18631.x/abstract Wiley-Blackwell Publishing Ltd. restricted |
| spellingShingle | radio continuum: general astronomical data bases: miscellaneous Bell, M. Fender, R. Swinbank, J. Miller-Jones, James Law, C. Scheers, B. Spreeuw, H. Wise, M. Stappers, B. Wijers, R. Hessels, J. Masters, J. An automated archival Very Large Array transients survey |
| title | An automated archival Very Large Array transients survey |
| title_full | An automated archival Very Large Array transients survey |
| title_fullStr | An automated archival Very Large Array transients survey |
| title_full_unstemmed | An automated archival Very Large Array transients survey |
| title_short | An automated archival Very Large Array transients survey |
| title_sort | automated archival very large array transients survey |
| topic | radio continuum: general astronomical data bases: miscellaneous |
| url | http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2966.2011.18631.x/abstract http://hdl.handle.net/20.500.11937/4477 |