An Arecibo 327 MHz Search for Radio Pulsars and Bursts in the Dwarf Irregular Galaxies Leo A and T

TL;DR

This study used the Arecibo telescope at 327 MHz to search for radio pulsars and bursts in the dwarf irregular galaxies Leo A and T, but found no signals, setting limits on detectable luminosities.

Contribution

First search for radio pulsars and bursts in Leo A and T galaxies at 327 MHz, establishing flux limits and implications for pulsar populations in these galaxies.

Findings

No astrophysical signals detected.

Luminosity limits suggest only the most luminous pulsars would be detectable.

Few or no extremely luminous pulsars are expected in Leo A and T.

Abstract

We have conducted an Arecibo 327 MHz search of two dwarf irregular galaxies in the Local Group, Leo A and T, for radio pulsars and single pulses from fast radio bursts and other giant pulse emitters. We detected no astrophysical signals in this search, and we estimate flux density limits on both periodic and burst emission. Our derived luminosity limits indicate that only the most luminous radio pulsars known in our Galaxy and in the Magellanic Clouds (MCs) would have been detectable in our search if they were at the distances of Leo A and T. Given the much smaller stellar mass content and star formation rates of Leo A and T compared to the Milky Way and the MCs, there are likely to be few (if any) extremely luminous pulsars in these galaxies. It is therefore not surprising that we detected no pulsars in our search.