The UTMOST pulsar timing programme – II. Timing noise across the pulsar population. Issue 1 (4th March 2020)

• Record Type: Journal Article
• Authors: Lower, M E; Bailes, M; Shannon, R M; Johnston, S; Flynn, C; Osłowski, S; Gupta, V; Farah, W; Bateman, T; Green, A J; Hunstead, R; Jameson, A; Jankowski, F; Parthasarathy, A; Price, D C; Sutherland, A; Temby, D; Venkatraman Krishnan, V
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 494:Issue 1(2020)
• Page Start: 228
• Page End: 245
• Publication Date: 2020-03-04
• Subjects: methods: data analysis -- astrometry -- ephemerides -- stars: neutron -- pulsars: general; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/staa615
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: While pulsars possess exceptional rotational stability, large-scale timing studies have revealed at least two distinct types of irregularities in their rotation: red timing noise and glitches. Using modern Bayesian techniques, we investigated the timing noise properties of 300 bright southern-sky radio pulsars that have been observed over 1.0–4.8 yr by the upgraded Molonglo Observatory Synthesis Telescope ( MOST ). We reanalysed the spin and spin-down changes associated with nine previously reported pulsar glitches, report the discovery of three new glitches and four unusual glitch-like events in the rotational evolution of PSR J1825−0935. We develop a refined Bayesian framework for determining how red noise strength scales with pulsar spin frequency (ν) and spin-down frequency ($\dot{\nu }$ ), which we apply to a sample of 280 non-recycled pulsars. With this new method and a simple power-law scaling relation, we show that red noise strength scales across the non-recycled pulsar population as $\nu ^{a} |\dot{\nu }|^{b}$, where $a = -0.84^{+0.47}_{-0.49}$ and $b = 0.97^{+0.16}_{-0.19}$ . This method can be easily adapted to utilize more complex, astrophysically motivated red noise models. Lastly, we highlight our timing of the double neutron star PSR J0737−3039, and the rediscovery of a bright radio pulsar originally found during the first Molonglo pulsar surveys with an incorrectly catalogued position.