Searching for pulsars, magnetars, and fast radio bursts in the sculptor galaxy using MeerKAT

authored by

H. Hurter, C. Venter, L. Levin, B. W. Stappers, E. D. Barr, R. P. Breton, S. Buchner, E. Carli, M. Kramer, P. V. Padmanabh, A. Possenti, V. Prayag, J. D. Turner

Abstract

The Sculptor Galaxy (NGC 253), located in the Southern Hemisphere, far off the Galactic Plane, has a relatively high star-formation rate of about 7 M_☉ yr⁻¹ and hosts a young and bright stellar population, including several super star clusters and supernova remnants. It is also the first galaxy, apart from the Milky Way Galaxy to be associated with two giant magnetar flares. As such, it is a potential host of pulsars and/or fast radio bursts in the nearby Universe. The instantaneous sensitivity and multibeam sky coverage offered by MeerKAT therefore make it a favourable target. We searched for pulsars, radio-emitting magnetars, and fast radio bursts in NGC 253 as part of the TRAPUM large survey project with MeerKAT. We did not find any pulsars during a 4 h observation, and derive a flux density limit of 4.4 μJy at 1400 MHz, limiting the pseudo-luminosity of the brightest putative pulsar in this galaxy to 54 Jy kpc². Assuming universality of pulsar populations between galaxies, we estimate that detecting a pulsar as bright as this limit requires NGC 253 to contain a pulsar population of ^∼_>20 000. We also did not detect any single pulses, and our single pulse search flux density limit is 62 mJy at 1284 MHz. Our search is sensitive enough to have detected any fast radio bursts and radio emission similar to the brighter pulses seen from the magnetar SGR J1935+2154 if they had occurred during our observation.

Organisation(s)

Institute of Gravitation Physics

External Organisation(s)

North-West University (NWU)
National Institute for Theoretical and Computational Sciences (NITheCS)
University of Manchester
Max Planck Institute for Radio Astronomy (MPIfR)
South African Radio Astronomy Observatory (SARAO)
Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
Istituto Nazionale di Astrofisica (INAF)
University of Cape Town (UCT)

Type

Article

Journal

Monthly Notices of the Royal Astronomical Society

Volume

533

Pages

4268-4273

No. of pages

6

ISSN

0035-8711

Publication date

05.08.2024

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Astronomy and Astrophysics, Space and Planetary Science

Electronic version(s)

https://doi.org/10.48550/arXiv.2408.01217 (Access: Open)
https://doi.org/10.1093/mnras/stae1880 (Access: Open)