6 papers
Is there a retrograde accretion disk around 4U 162667? Tracking torque reversals with a state-space model
Joseph O'Leary, Andrew Melatos, Tom Kimpson +5
X-ray timing studies of the persistent, Galactic, accretion-powered pulsar 4U 162667 reveal torque reversals, during which the pulse frequency alternates between multiye…
Measuring the crust-superfluid coupling time-scale for 105 UTMOST pulsars with a Kalman filter
Wenhao Dong, Andrew Melatos, Nicholas J. O'Neill +2
Crust-superfluid coupling plays an important role in neutron star rotation, particularly with respect to timing noise and glitches. Here, we present new timing-noise-based estimate…
Argus: JAX state-space filtering for gravitational wave detection with a pulsar timing array
Tom Kimpson, Nicholas J. O'Neill, Patrick M. Meyers +1
Argus is a high-performance Python package for detecting and characterising nanohertz gravitational waves in pulsar timing array data. The package provides a complete Bayesian infe…
Observing Rayleigh-Taylor stable and unstable accretion through a Kalman filter analysis of X-ray pulsars in the Small Magellanic Cloud
Joseph O'Leary, Andrew Melatos, Tom Kimpson +5
Global, three-dimensional, magnetohydrodynamic simulations of Rayleigh-Taylor instabilities at the disk-magnetosphere boundary of rotating, magnetized, compact stellar objects reve…
State-space algorithm for detecting the nanohertz gravitational wave background
Tom Kimpson, Andrew Melatos, Joseph O'Leary +11
The stochastic gravitational wave background (SGWB) can be observed in the nanohertz band using a pulsar timing array (PTA). Here a computationally efficient state-space framework…
State-space analysis of a continuous gravitational wave source with a pulsar timing array: inclusion of the pulsar terms
Tom Kimpson, Andrew Melatos, Joseph O'Leary +11
Pulsar timing arrays can detect continuous nanohertz gravitational waves emitted by individual supermassive black hole binaries. The data analysis procedure can be formulated withi…