Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager

We present one of the best sampled early-time light curves of a gamma-ray burst (GRB) at radio wavelengths. Using the Arcminute Mircrokelvin Imager (AMI), we observed GRB 130427A at the central frequency of 15.7 GHz between 0.36 and 59.32 d post-burst. These results yield one of the earliest radio d...

Full description

Bibliographic Details
Main Authors: Anderson, Gemma, Van der horst, A., Staley, T., Fender, R., Wijers, R., Scaife, A., Rumsey, C., Titterington, D., Rowlinson, A., Saunders, R.
Format: Journal Article
Published: Oxford University Press 2014
Online Access:http://hdl.handle.net/20.500.11937/52659
_version_ 1848758980092887040
author Anderson, Gemma
Van der horst, A.
Staley, T.
Fender, R.
Wijers, R.
Scaife, A.
Rumsey, C.
Titterington, D.
Rowlinson, A.
Saunders, R.
author_facet Anderson, Gemma
Van der horst, A.
Staley, T.
Fender, R.
Wijers, R.
Scaife, A.
Rumsey, C.
Titterington, D.
Rowlinson, A.
Saunders, R.
author_sort Anderson, Gemma
building Curtin Institutional Repository
collection Online Access
description We present one of the best sampled early-time light curves of a gamma-ray burst (GRB) at radio wavelengths. Using the Arcminute Mircrokelvin Imager (AMI), we observed GRB 130427A at the central frequency of 15.7 GHz between 0.36 and 59.32 d post-burst. These results yield one of the earliest radio detections of a GRB and demonstrate a clear rise in flux less than one day after the ?-ray trigger followed by a rapid decline. This early-time radio emission probably originates in the GRB reverse shock so our AMI light curve reveals the first ever confirmed detection of a reverse shock peak in the radio domain. At later times (about 3.2 d post-burst), the rate of decline decreases, indicating that the forward shock component has begun to dominate the light curve. Comparisons of the AMI light curve with modelling conducted by Perley et al. show that the most likely explanation of the early-time 15.7 GHz peak is caused by the self-absorption turn-over frequency, rather than the peak frequency, of the reverse shock moving through the observing bands. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.
first_indexed 2025-11-14T09:52:36Z
format Journal Article
id curtin-20.500.11937-52659
institution Curtin University Malaysia
institution_category Local University
last_indexed 2025-11-14T09:52:36Z
publishDate 2014
publisher Oxford University Press
recordtype eprints
repository_type Digital Repository
spelling curtin-20.500.11937-526592017-09-13T15:39:44Z Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager Anderson, Gemma Van der horst, A. Staley, T. Fender, R. Wijers, R. Scaife, A. Rumsey, C. Titterington, D. Rowlinson, A. Saunders, R. We present one of the best sampled early-time light curves of a gamma-ray burst (GRB) at radio wavelengths. Using the Arcminute Mircrokelvin Imager (AMI), we observed GRB 130427A at the central frequency of 15.7 GHz between 0.36 and 59.32 d post-burst. These results yield one of the earliest radio detections of a GRB and demonstrate a clear rise in flux less than one day after the ?-ray trigger followed by a rapid decline. This early-time radio emission probably originates in the GRB reverse shock so our AMI light curve reveals the first ever confirmed detection of a reverse shock peak in the radio domain. At later times (about 3.2 d post-burst), the rate of decline decreases, indicating that the forward shock component has begun to dominate the light curve. Comparisons of the AMI light curve with modelling conducted by Perley et al. show that the most likely explanation of the early-time 15.7 GHz peak is caused by the self-absorption turn-over frequency, rather than the peak frequency, of the reverse shock moving through the observing bands. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. 2014 Journal Article http://hdl.handle.net/20.500.11937/52659 10.1093/mnras/stu478 Oxford University Press unknown
spellingShingle Anderson, Gemma
Van der horst, A.
Staley, T.
Fender, R.
Wijers, R.
Scaife, A.
Rumsey, C.
Titterington, D.
Rowlinson, A.
Saunders, R.
Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title_full Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title_fullStr Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title_full_unstemmed Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title_short Probing the bright radio flare and afterglow of GRB 130427A with the arcminute microkelvin imager
title_sort probing the bright radio flare and afterglow of grb 130427a with the arcminute microkelvin imager
url http://hdl.handle.net/20.500.11937/52659