The FRB 20121102A November rain in 2018 observed with the Arecibo Telescope
ABSTRACT

We present 849 new bursts from FRB 20121102A detected with the 305-m Arecibo Telescope. Observations were conducted as part of our regular campaign to monitor activity and evolution of burst properties. The 10 reported observations were carried out between 1150 and $1730\, {\rm MHz}$ and fall in the active period around 2018 November. All bursts were dedispersed at the same dispersion measure and are consistent with a single value of $(562.4 \pm 0.1)\, {\rm pc\, cm^{-3}}$. The rate varies between 0 bursts and 218 ± 16 bursts per hour, the highest rate observed to date. The times between consecutive bursts show a bimodal distribution. We find that a Poisson process with varying rate best describes arrival times with separations ${\gt}{0.1\, {\rm s}}$. Clustering on time-scales of $22\, {\rm ms}$ reflects a characteristic time-scale of the source and possibly the emission mechanism. We analyse the spectro-temporal structure of the bursts by fitting 2D Gaussians with a temporal drift to each sub-burst in the dynamic spectra. We find a linear relationship between the sub-burst’s drift and its duration. At the same time, the drifts are consistent with coming from the sad-trombone effect. This has not been predicted by current models. The energy distribution shows more »

Authors:
; ; ; ; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10387053
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
519
Issue:
1
Page Range or eLocation-ID:
p. 666-687
ISSN:
0035-8711
Publisher:
Oxford University Press
National Science Foundation
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