CaltechAUTHORS
  A Caltech Library Service

Implications from ASKAP Fast Radio Burst Statistics

Lu, Wenbin and Piro, Anthony L. (2019) Implications from ASKAP Fast Radio Burst Statistics. Astrophysical Journal, 883 (1). Art. No. 40. ISSN 1538-4357. https://resolver.caltech.edu/CaltechAUTHORS:20190919-112116256

[img] PDF - Published Version
See Usage Policy.

931Kb
[img] PDF - Submitted Version
See Usage Policy.

4Mb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20190919-112116256

Abstract

Although there has recently been tremendous progress in studies of fast radio bursts (FRBs), the nature of their progenitors remains a mystery. We study the fluence and dispersion measure (DM) distributions of the ASKAP sample to better understand their energetics and statistics. We first consider a simplified model of a power-law volumetric rate per unit isotropic energy dN/dE ∝ E^(−γ) with a maximum energy E_(max) in a uniform Euclidean universe. This provides analytic insights for what can be learned from these distributions. We find that the observed cumulative DM distribution scales as N(>DM) ∝ DM^(5−2γ) (for γ > 1) until a maximum DMmax above which bursts near E_(max) fall below the fluence threshold of a given telescope. Comparing this model with the observed fluence and DM distributions, we find a reasonable fit for γ ~ 1.7 and E_(max) ~ 10^(33) erg Hz^(−1). We then carry out a full Bayesian analysis based on a Schechter rate function with cosmological factors. We find roughly consistent results with our analytical approach, although with large errors on the inferred parameters due to the small sample size. The power-law index and the maximum energy are constrained to be γ ≃ 1.6 ± 0.3 and log(E_(max)) [erg/Hz] ≃ 34.1^(+1.1)_(-0.7) (68% confidence), respectively. From the survey exposure time, we further infer a cumulative local volumetric rate of log N(E > 10^(32) erg/Hz) [Gpc^(-3) yr^(-1)] ≃ 2.6 ± 0.4 (68% confidence). The methods presented here will be useful for the much larger FRB samples expected in the near future to study their distributions, energetics, and rates.


Item Type:Article
Related URLs:
URLURL TypeDescription
https://doi.org/10.3847/1538-4357/ab3796DOIArticle
https://arxiv.org/abs/1903.00014arXivDiscussion Paper
ORCID:
AuthorORCID
Lu, Wenbin0000-0002-1568-7461
Piro, Anthony L.0000-0001-6806-0673
Additional Information:© 2019 The American Astronomical Society. Received 2019 February 27; revised 2019 June 24; accepted 2019 July 30; published 2019 September 18. We thank the two anonymous referees for carefully reading the manuscript and providing valuable criticisms and suggestions. We thank Jonathan Katz, Liam Connor, and Ue-Li Pen for useful comments. W.L. is supported by the David and Ellen Lee Fellowship at Caltech.
Group:TAPIR, Walter Burke Institute for Theoretical Physics
Funders:
Funding AgencyGrant Number
David and Ellen Lee Postdoctoral ScholarshipUNSPECIFIED
Subject Keywords:methods: analytical – radio continuum: general
Issue or Number:1
Record Number:CaltechAUTHORS:20190919-112116256
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20190919-112116256
Official Citation:Wenbin Lu and Anthony L. Piro 2019 ApJ 883 40
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:98743
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:19 Sep 2019 18:45
Last Modified:03 Oct 2019 21:43

Repository Staff Only: item control page