Reinvestigation of Fast Radio Burst Host Galaxy and Event Rate Density

TL;DR

This study analyzes FRB host galaxies and event rate densities, revealing the impact of host galaxy dispersion measures on FRB population origins using CHIME/FRB data and statistical modeling.

Contribution

It provides the first comprehensive analysis of FRB host galaxy properties and their influence on volumetric rate estimates, improving understanding of FRB progenitors.

Findings

No significant difference in median host DM between repeaters and non-repeaters.

Host galaxy DM significantly influences volumetric rate estimates.

Results constrain FRB origin models and their relation to transient events.

Abstract

Fast radio bursts (FRBs) are radio signals that last milliseconds. They originate from cosmological distances and have relatively high dispersion measures (DMs), making them being excellent distance indicators. However, the origins of the FRB remain to be resolved. With its wide field of view and excellent sensitivity, CHIME/FRB has discovered more than half of all known FRBs. As more and more FRBs are located within or connected with their host galaxies, the study of FRB progenitors is becoming more important. In this work, we collect the currently available information related to the host galaxies of FRBs, and the Markov Chain Monte Carlo analysis about limited localized samples reveals no significant difference in the median of $\mathrm{DM_{host}}$ between repeaters and non-repeaters. After examining and selecting CHIME/FRB samples, we estimate the local volumetric rate density of repeaters and non-repeaters, accounting for different $\mathrm{DM_{host}}$ contributions, and compare with rates of predicted origin models and transient events. Our results indicate that $\mathrm{DM_{host}}$ significantly affects volumetric rates and offer insights into the origin mechanisms of FRB populations.