Properties and observability of glitches and anti-glitches in accreting pulsars

Abstract

Several glitches have been observed in young, isolated radio pulsars, while a clear detection in accretion-powered X-ray pulsars is still lacking. We use the Pizzochero snowplow model for pulsar glitches as well as starquake models to determine for the first time the expected properties of glitches in accreting pulsars and their observability. Since some accreting pulsars show accretion-induced long-term spin-up, we also investigate the possibility that anti-glitches occur in these stars. We find that glitches caused by quakes in a slow accreting neutron star are very rare and their detection extremely unlikely. On the contrary, glitches and anti-glitches caused by a transfer of angular momentum between the superfluid neutron vortices and the non-superfluid component may take place in accreting pulsars more often. We calculate the maximum jump in angular velocity of an anti-glitch and we find that it is expected to be about 1E-5 - 1E-4 rad/s. We also note that since accreting pulsars usually have rotational angular velocities lower than those of isolated glitching pulsars, both glitches and anti-glitches are expected to have long rise and recovery timescales compared to isolated glitching pulsars, with glitches and anti-glitches appearing as a simple step in angular velocity. Among accreting pulsars, we find that GX 1+4 is the best candidate for the detection of glitches with currently operating X-ray instruments and future missions such as the proposed Large Observatory for X-ray Timing (LOFT).

arXiv commentAccepted for publication in Astronomy & Astrophysics. 6 pages. Minor changes to match the final A&A version

References in corpus (24)

• Observations of Accreting Pulsars
• A study of 315 glitches in the rotation of 102 pulsars
• Models of Pulsar Glitches
• Detection of 107 glitches in 36 southern pulsars
• High time resolution observations of the January 2000 glitch in the Vela pulsar
• On the Dramatic Spin-up/Spin-down Torque Reversals in Accreting Pulsars
• A Glitch in an Anomalous X-ray Pulsar
• Modelling pulsar glitches with realistic pinning forces: a hydrodynamical approach
• A Frequency Glitch in an Accreting Pulsar
• Orbital Decay and Evidence of Disk Formation in the X-ray Binary Pulsar OAO 1657-415
• Angular Momentum Transfer in Vela-like Pulsar Glitches
• 1S0 Proton and Neutron Superfluidity in beta-stable Neutron Star Matter
• Spin period evolution of GX 1+4
• Narrow-band search of continuous gravitational-wave signals from Crab and Vela pulsars in Virgo VSR4 data
• INTEGRAL observations of the variability of OAO 1657-415
• Glitch recoveries in radio-pulsars and magnetars
• Torque reversals and pulse profile of the pulsar 4U 1626-67
• The effect of realistic equations of state and general relativity on the "snowplow" model for pulsar glitches
• Deformation and crustal rigidity of rotating neutron stars
• Recent Torque Reversal of 4U 1907+09
• Continuous monitoring of pulse period variations in Her X-1 using Swift/BAT
• Recent activity of the Be/X-ray binary system SAX J2103.5+4545
• Long-Term Timing and Glitch Characteristics of Anomalous X-ray Pulsar 1RXS J170849.0-400910
• A diagnosis on torque reversals in 4U 1626-67

Cited by in corpus (7)

• Anti-glitches in the Ultraluminous Accreting Pulsar NGC 300 ULX-1 Observed with NICER
• Discovery of a Glitch in the Accretion Powered Pulsar SXP 1062
• Discovery of the first anti-glitch event in the rotation-powered pulsar PSR B0540-69
• Gapless neutron superfluidity can explain the late time cooling of transiently accreting neutron stars
• Continuous gravitational wave emission from neutron stars with pinned superfluids in the core
• Continuous gravitational waves from trapped magnetar ejecta and the connection to glitches and antiglitches
• The unusual behaviour of the young X-ray pulsar SXP 1062 during the 2019 outburst