We present a catalog of 536 fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst (CHIME/FRB) Project between 400 and 800 MHz from 2018 July 25 to 2019 July 1, including 62 bursts from 18 previously reported repeating sources. The catalog represents the first large sample, including bursts from repeaters and nonrepeaters, observed in a single survey with uniform selection effects. This facilitates comparative and absolute studies of the FRB population. We show that repeaters and apparent nonrepeaters have sky locations and dispersion measures (DMs) that are consistent with being drawn from the same distribution. However, bursts from repeating sources differ from apparent nonrepeaters in intrinsic temporal width and spectral bandwidth. Through injection of simulated events into our detection pipeline, we perform an absolute calibration of selection effects to account for systematic biases. We find evidence for a population of FRBs—composing a large fraction of the overall population—with a scattering time at 600 MHz in excess of 10 ms, of which only a small fraction are observed by CHIME/FRB. We infer a power-law index for the cumulative fluence distribution of
We introduce a toy model for the time–frequency structure of fast radio bursts, in which the observed emission is produced as a narrowly peaked intrinsic spectral energy distribution sweeps down in frequency across the instrumental bandpass as a power law in time. Though originally motivated by emission models that invoke a relativistic shock, the model could in principle apply to a wider range of emission scenarios. We quantify the burst’s detectability using the frequency bandwidth over which most of its signal-to-noise ratio is accumulated. We demonstrate that, by varying just a single parameter of the toy model—the power-law index
- Publication Date:
- NSF-PAR ID:
- 10362392
- Journal Name:
- The Astrophysical Journal
- Volume:
- 925
- Issue:
- 2
- Page Range or eLocation-ID:
- Article No. 135
- ISSN:
- 0004-637X
- Publisher:
- DOI PREFIX: 10.3847
- Sponsoring Org:
- National Science Foundation
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