MeerKAT caught a Mini Mouse: serendipitous detection of a young radio pulsar escaping its birth site

Journal article

In MeerKAT observations pointed at a Galactic X-ray binary located on the Galactic plane, we serendipitously discovered a radio nebula with cometary-like morphology. The feature, which we named 'the Mini Mouse' based on its similarity with the previously discovered 'Mouse' nebula, points back towards the previously unidentified candidate supernova remnant G45.24+0.18. We observed the location of the Mini Mouse with MeerKAT in two different observations, and we localized with arcsecond precision the 138-ms radio pulsar PSR J1914+1054g, recently discovered by the FAST telescope, to a position consistent with the head of the nebula. We confirm a dispersion measure of about 418 pc cm-3 corresponding to a distance between 7.8 and 8.8 kpc based on models of the electron distribution. Using our accurate localization and two period measurements spaced 90 d apart, we calculate a period derivative of (2.7 ± 0.3) × 10 -14 s s-1. We derive a characteristic age of approximately 82 kyr and a spin-down luminosity of 4 × 1035 erg s-1. For a pulsar age comparable with the characteristic age, we find that the projected velocity of the neutron star is between 320 and 360 km s-1 if it was born at the location of the supernova remnant. The size of the proposed remnant appears small if compared with the pulsar characteristic age; however, the relatively high density of the environment near the Galactic plane could explain a suppressed expansion rate and thus a smaller remnant.

Authors: Motta, SE; Turner, JD; Stappers, B; Fender, RP; Heywood, I

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Oxford University Press
• Journal: Monthly Notices of the Royal Astronomical Society
• Volume: 523
• Issue: 2
• Pages: 2850-2857
• Publication date: 2023-05-12
• Acceptance date: 2023-05-08
• DOI: 10.1093/mnras/stad1438
• EISSN: 1365-2966
• ISSN: 0035-8711
• Language: English
• Keywords: 5101 Astronomical Sciences; FFR; 51 Physical Sciences