DSA-2000 Collaboration

The stellar population in the neighborhood of extragalactic transients and their delay-time distributions provide critical insights into their progenitor physics. Historically, such statistical endeavors have played a crucial role in unveiling the nature of progenitors of several transients, such as gamma-ray bursts and supernovae. The venture of characterizing host galaxies of Fast Radio Bursts (FRBs) is essential to disentangle the proposed spectrum of formation channels, ranging from young magnetars formed during core-collapse supernovae to binary neutron star mergers in early-type galaxies. The major challenge in achieving this goal is to obtain their sub-arcsecond localizations. The Deep Synoptic Array-2000 (DSA-2000) aims to bridge this gap by enabling precision localizations with sustained, high-speed monitoring at an FRB discovery rate of 2,000/year.

The host galaxy of FRB 20220509G is a massive, red, dead, early-type elliptical galaxy. This is one of its type FRB host in the know plethora of FRB host environments, thus further diversifying their host stellar environments. The spectrum of this host exhibits negligible nebular emission features with significant absorption features, which is a characteristic of an old stellar population. The spectral energy distribution of this galaxy reveals negligible ongoing star formation, thus hinting at multiple formation channels of Fast Radio Bursts, apart from Core-Collapse Supernovae, which are more likely to occur in star-forming environments. A detailed discussion on the delay-time distribution of FRBs, checkout Sharma et al. (2023)!