The TRAPUM L-band survey for pulsars in Fermi-LAT gamma-ray sources. Issue 4 (6th January 2023)

• Record Type: Journal Article
• Authors: Clark, C J; Breton, R P; Barr, E D; Burgay, M; Thongmeearkom, T; Nieder, L; Buchner, S; Stappers, B; Kramer, M; Becker, W; Mayer, M; Phosrisom, A; Ashok, A; Bezuidenhout, M C; Calore, F; Cognard, I; Freire, P C C; Geyer, M; Grießmeier, J-M; Karuppusamy, R; Levin, L; Padmanabh, P V; Possenti, A; Ransom, S; Serylak, M; Venkatraman Krishnan, V; Vleeschower, L; Behrend, J; Champion, D J; Chen, W; Horn, D; Keane, E F; Künkel, L; Men, Y; Ridolfi, A; Dhillon, V S; Marsh, T R; Papa, M A;
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 519:Issue 4(2023)
• Page Start: 5590
• Page End: 5606
• Publication Date: 2023-01-06
• Subjects: binaries: general -- pulsars: general -- pulsars: individual: J1036−4353, J1526−2744, J1803−6707 -- gamma rays: stars; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stac3742
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: More than 100 millisecond pulsars (MSPs) have been discovered in radio observations of gamma-ray sources detected by the Fermi Large Area Telescope (LAT), but hundreds of pulsar-like sources remain unidentified. Here, we present the first results from the targeted survey of Fermi -LAT sources being performed by the Transients and Pulsars with MeerKAT (TRAPUM) Large Survey Project. We observed 79 sources identified as possible gamma-ray pulsar candidates by a Random Forest classification of unassociated sources from the 4FGL catalogue. Each source was observed for 10 min on two separate epochs using MeerKAT's L -band receiver (856–1712 MHz), with typical pulsed flux density sensitivities of $\sim 100\, \mu$ Jy. Nine new MSPs were discovered, eight of which are in binary systems, including two eclipsing redbacks and one system, PSR J1526−2744, that appears to have a white dwarf companion in an unusually compact 5 h orbit. We obtained phase-connected timing solutions for two of these MSPs, enabling the detection of gamma-ray pulsations in the Fermi -LAT data. A follow-up search for continuous gravitational waves from PSR J1526−2744 in Advanced LIGO data using the resulting Fermi -LAT timing ephemeris yielded no detection, but sets an upper limit on the neutron star ellipticity of 2.45 × 10 −8 . We also detected X-ray emission from the redback PSR J1803−6707 in data from the first eROSITA all-sky survey, likely due to emission from an intrabinary shock.