30 citations · 118 across the 21 of their papers we have counts for
23 papers
Detecting AI Training in Datacentre Power
Tom Kimpson, Mauricio Baker, Emlyn Graham
AI governance agreements require methods to detect large model training runs on a monitored computing cluster, without trusting the operator. We develop a method to detect synchron…
Can Power Draw Constrain Covert Compute? Limits of Analogue Verification for AI Governance
Tom Kimpson, Mauricio Baker, Emlyn Graham
Frontier AI treaties or agreements on limiting computation require external verification; an external auditor must be able to confirm how much computation actually ran and that par…
Narrow spectral artifact investigation and mitigation in LIGO data from the fourth LIGO-Virgo-KAGRA observing run
E. Goetz, A. Neunzert, A. M. Knee +258
We present efforts to identify, characterize, and mitigate narrow spectral artifacts in LIGO detector data during the fourth LIGO-Virgo-KAGRA observing run. Narrow spectral artifac…
Temporal Memory in Repeating Fast Radio Bursts: Epsilon-Machine Reconstruction of Causal Structure in Burst Timing
Tom Kimpson, Joseph O'Leary
The emission mechanism of fast radio bursts (FRBs) remains unknown. Whether the bursts from a repeating FRB arrive at random or in a structured sequence is a key constraint on that…
Reduced-Precision Stochastic Simulation for Mathematical Biology
Tom Kimpson, Mark B. Flegg, Jennifer A. Flegg
The stochastic simulation algorithm (SSA) is widely used to perform exact forward simulation of discrete stochastic processes in biology. However, the computational cost, driven by…
Search for continuous gravitational waves from neutron stars in five globular clusters in the first part of the fourth LIGO-Virgo-KAGRA observing run
Damon H. T. Cheung, Keith Riles, Rafel Amengual +15
We present the results of directed searches for continuous gravitational waves from unknown neutron stars in five Milky Way globular clusters. We carry out these searches in the LI…
Multiscale Modelling of Birth-Death Processes
Tom Kimpson, Domenic P. J. Germano, Jennifer A. Flegg +1
Many biological systems exhibit multiscale dynamics, where some species occur in high copy numbers while others remain rare. This heterogeneity necessitates hybrid modelling approa…
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 multiyea…
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…
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…
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…
Adaptive cancellation of mains power interference in continuous gravitational wave searches with a hidden Markov model
Tom Kimpson, Sofia Suvorova, Hannah Middleton +4
Continuous gravitational wave searches with terrestrial, long-baseline interferometers are hampered by long-lived, narrowband features in the power spectral density of the detector…
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…
Kalman tracking and parameter estimation of continuous gravitational waves with a pulsar timing array
Tom Kimpson, Andrew Melatos, Joseph O'Leary +11
Continuous nanohertz gravitational waves from individual supermassive black hole binaries may be detectable with pulsar timing arrays. A novel search strategy is developed, wherein…
Measuring the magnetic dipole moment and magnetospheric fluctuations of accretion-powered pulsars in the Small Magellanic Cloud with an unscented Kalman filter
Joseph O'Leary, Andrew Melatos, Tom Kimpson +5
Many accretion-powered pulsars rotate in magnetocentrifugal disequilibrium, spinning up or down secularly over multi-year intervals. The magnetic dipole moment of such systems…
RelativisticDynamics.jl: Relativistic Spin-Orbital Dynamics in Julia
Tom Kimpson
RelativisticDynamics.jl is an open-source Julia package for relativistic spin-orbital dynamics in the gravitational strong-field of a Kerr spacetime. Existing codes for modelling t…
Deep learning for quality control of surface physiographic fields using satellite Earth observations
Tom Kimpson, Margarita Choulga, Matthew Chantry +4
A purposely built deep learning algorithm for the Verification of Earth-System ParametERisation (VESPER) is used to assess recent upgrades of the global physiographic datasets unde…
Climate Change Modelling at Reduced Float Precision with Stochastic Rounding
Tom Kimpson, E. Adam Paxton, Matthew Chantry +1
Reduced precision floating point arithmetic is now routinely deployed in numerical weather forecasting over short timescales. However the applicability of these reduced precision t…
Radio timing in a millisecond pulsar-extreme/intermediate mass ratio binary system
Tom Kimpson, Kinwah Wu, Silvia Zane
Radio timing observations of a millisecond pulsar in orbit around the Galactic centre black hole (BH) or a BH at the centre of globular clusters could answer foundational questions…
Orbital spin dynamics of a millisecond pulsar around a massive black hole with an general mass quadrupole
Tom Kimpson, Kinwah Wu, Silvia Zane
We investigate the spin dynamics of a millisecond pulsar (MSP) in compact orbit around a Kerr-like massive black hole with an general mass quadrupole. We use the Mathisson-Papetrou…
Gravitational Burst Radiation from Pulsars in the Galactic centre and stellar clusters
Tom Kimpson, Kinwah Wu, Silvia Zane
Pulsars (PSRs) orbiting intermediate or supermassive black holes at the centre of galaxies and globular clusters are known as Extreme Mass Ratio Binaries (EMRBs) and have been iden…
Pulsar timing in extreme mass ratio binaries: a general relativistic approach
Tom Kimpson, Kinwah Wu, Silvia Zane
The detection of a pulsar (PSR) in a tight, relativistic orbit around a supermassive or intermediate mass black hole - such as those in the Galactic centre or in the centre of Glob…
Spatial dispersion of light rays propagating through a plasma in Kerr spacetime
Tom Kimpson, Kinwah Wu, Silvia Zane
We investigate the propagation of light through a plasma on a background Kerr spacetime via a Hamiltonian formulation. The behaviour of light when propagating through a vacuum and…