Modelling DSA, FAST and CRAFT surveys in a z-DM analysis and constraining a minimum FRB energy

TL;DR

This study models FRB populations using multiple surveys, incorporates new data and uncertainties, and constrains the minimum FRB energy, revealing potential differences in luminosity functions.

Contribution

It introduces a combined analysis of DSA, FAST, and other surveys with MCMC and Galactic DM uncertainties, refining FRB population and energy constraints.

Findings

Refined minimum FRB energy: logE_min ≈ 39.49 erg.

Predicted high-redshift detection rates for FAST and DSA.

Larger uncertainties in parameters due to Galactic DM uncertainties.

Abstract

Fast radio burst (FRB) science primarily revolves around two facets: the origin of these bursts and their use in cosmological studies. This work follows from previous redshift-dispersion measure ($z$-DM) analyses in which we model instrumental biases and simultaneously fit population parameters and cosmological parameters to the observed population of FRBs. This sheds light on both the progenitors of FRBs and cosmological questions. Previously, we have completed similar analyses with data from the Australian Square Kilometer Array Pathfinder (ASKAP) and the Murriyang (Parkes) Multibeam system. With this manuscript, we additionally incorporate data from the Deep Synoptic Array (DSA) and the Five-hundred-meter Aperture Spherical Telescope (FAST), invoke a Markov chain Monte Carlo (MCMC) sampler and implement uncertainty in the Galactic DM contributions. The latter leads to larger uncertainties in derived model parameters than previous estimates despite the additional data. We provide refined constraints on FRB population parameters and derive a new constraint on the minimum FRB energy of log$\,E_{\mathrm{min}}$(erg)=39.49$^{+0.39}_{-1.48}$ which is significantly higher than bursts detected from strong repeaters. This result may indicate a low-energy turnover in the luminosity function or may suggest that strong repeaters have a different luminosity function to single bursts. We also predict that FAST will detect 25-41% of their FRBs at $z \gtrsim 2$ and DSA will detect 2-12% of their FRBs at $z \gtrsim 1$.