The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz
We present the Arcminute Microkelvin Imager (AMI) Large Array catalogue of 139 gamma-ray bursts (GRBs). AMI observes at a central frequency of 15.7 GHz and is equipped with a fully automated rapid-response mode, which enables the telescope to respond to high-energy transients detected by Swift. On r...
| Main Authors: | , , , , , , , , , |
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| Format: | Journal Article |
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Oxford University Press
2018
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| Online Access: | http://hdl.handle.net/20.500.11937/67949 |
| _version_ | 1848761701072109568 |
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| author | Anderson, Gemma Staley, T. van der Horst, A. Fender, R. Rowlinson, A. Mooley, K. Broderick, J. Wijers, R. Rumsey, C. Titterington, D. |
| author_facet | Anderson, Gemma Staley, T. van der Horst, A. Fender, R. Rowlinson, A. Mooley, K. Broderick, J. Wijers, R. Rumsey, C. Titterington, D. |
| author_sort | Anderson, Gemma |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | We present the Arcminute Microkelvin Imager (AMI) Large Array catalogue of 139 gamma-ray bursts (GRBs). AMI observes at a central frequency of 15.7 GHz and is equipped with a fully automated rapid-response mode, which enables the telescope to respond to high-energy transients detected by Swift. On receiving a transient alert, AMI can be on-target within 2 min, scheduling later start times if the source is below the horizon. Further AMI observations are manually scheduled for several days following the trigger. The AMI GRB programme probes the early-time (<1 d) radio properties of GRBs, and has obtained some of the earliest radio detections (GRB 130427A at 0.36 and GRB 130907A at 0.51 d post-burst). As all Swift GRBs visible to AMI are observed, this catalogue provides the first representative sample of GRB radio properties, unbiased by multiwavelength selection criteria. We report the detection of six GRB radio afterglows that were not previously detected by other radio telescopes, increasing the rate of radio detections by 50 per cent over an 18-month period. The AMI catalogue implies a Swift GRB radio detection rate of ≳ 15 per cent, down to ∼0.2 mJy beam−1. However, scaling this by the fraction of GRBs AMI would have detected in the Chandra & Frail sample (all radio-observed GRBs between 1997 and 2011), it is possible ∼ 44–56 per cent of Swift GRBs are radio bright, down to ∼0.1–0.15 mJy beam−1. This increase from the Chandra & Frail rate (∼30 per cent) is likely due to the AMI rapid-response mode, which allows observations to begin while the reverse-shock is contributing to the radio afterglow. |
| first_indexed | 2025-11-14T10:35:51Z |
| format | Journal Article |
| id | curtin-20.500.11937-67949 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:35:51Z |
| publishDate | 2018 |
| publisher | Oxford University Press |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-679492018-09-26T06:31:24Z The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz Anderson, Gemma Staley, T. van der Horst, A. Fender, R. Rowlinson, A. Mooley, K. Broderick, J. Wijers, R. Rumsey, C. Titterington, D. We present the Arcminute Microkelvin Imager (AMI) Large Array catalogue of 139 gamma-ray bursts (GRBs). AMI observes at a central frequency of 15.7 GHz and is equipped with a fully automated rapid-response mode, which enables the telescope to respond to high-energy transients detected by Swift. On receiving a transient alert, AMI can be on-target within 2 min, scheduling later start times if the source is below the horizon. Further AMI observations are manually scheduled for several days following the trigger. The AMI GRB programme probes the early-time (<1 d) radio properties of GRBs, and has obtained some of the earliest radio detections (GRB 130427A at 0.36 and GRB 130907A at 0.51 d post-burst). As all Swift GRBs visible to AMI are observed, this catalogue provides the first representative sample of GRB radio properties, unbiased by multiwavelength selection criteria. We report the detection of six GRB radio afterglows that were not previously detected by other radio telescopes, increasing the rate of radio detections by 50 per cent over an 18-month period. The AMI catalogue implies a Swift GRB radio detection rate of ≳ 15 per cent, down to ∼0.2 mJy beam−1. However, scaling this by the fraction of GRBs AMI would have detected in the Chandra & Frail sample (all radio-observed GRBs between 1997 and 2011), it is possible ∼ 44–56 per cent of Swift GRBs are radio bright, down to ∼0.1–0.15 mJy beam−1. This increase from the Chandra & Frail rate (∼30 per cent) is likely due to the AMI rapid-response mode, which allows observations to begin while the reverse-shock is contributing to the radio afterglow. 2018 Journal Article http://hdl.handle.net/20.500.11937/67949 10.1093/mnras/stx2407 Oxford University Press fulltext |
| spellingShingle | Anderson, Gemma Staley, T. van der Horst, A. Fender, R. Rowlinson, A. Mooley, K. Broderick, J. Wijers, R. Rumsey, C. Titterington, D. The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title | The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title_full | The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title_fullStr | The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title_full_unstemmed | The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title_short | The Arcminute Microkelvin Imager catalogue of gamma-ray burst afterglows at 15.7 GHz |
| title_sort | arcminute microkelvin imager catalogue of gamma-ray burst afterglows at 15.7 ghz |
| url | http://hdl.handle.net/20.500.11937/67949 |