I am a research fellow in the Solar and Magnetospheric Theory Group in the School of Mathematics and Statistics at the University of St Andrews, where I study magnetohydrodynamic (MHD) waves in the solar corona. I use numerical simulations to model how waves travel through large-scale coronal structures such as helmet streamers, and compare the results with observations from instruments such as the Metis coronagraph on Solar Orbiter.
Before this I was a research fellow in the School of Physics and Astronomy at St Andrews (2021–2025), working on stellar prominences and coronal rain: how cool, dense material condenses in the magnetic fields of stars, and what happens when it is ejected or falls back to the stellar surface.
I graduated from the University of York in 2014 with a first-class MPhys in Theoretical Physics, and completed my PhD in astrophysics in 2018. I then held postdoctoral positions at Maison de la Simulation, CEA Saclay, Paris, simulating convection in exoplanet atmospheres, and at the Cavendish Laboratory, University of Cambridge, developing software for the Square Kilometre Array.
A 3D global model of the solar corona (Carrington rotation 2269) with MHD waves propagating through it. The volume renderings show the slow, fast and Alfvén wave modes, and the lines trace closed and open magnetic field.
The interactive model is about 30 MB and works best on a desktop. Drag to rotate, scroll to zoom, and use “Show/hide” to toggle each part (You may need to move the model for it to appear the first time after activating). Open full screen
Thermal radio emission generated in the wind of a 26 solar mass star. The winds of these massive stars are dense, hot regions that produce bright, detectable radio emission. This simulation explores the impact that magnetic fields have on the emission structure of the wind.
Planetary wind material interacting with the magnetic field of a solar-type star. The plasma of the planetary wind forms arching structures as it follows the magnetic field lines and is drawn down to the stellar surface by the star's gravity.
Magnetosphere of a hot Jupiter exoplanet embedded in the wind of its host star. The red stream lines show the stellar wind and the blue-red stream lines the planetary magnetic field. The green cloud is the material lost by the planet due to the star's intense FUV radiation.
The effective radius of a massive star's wind, as seen by an observer, at different observing frequencies. The two curves show the case when the acceleration of the wind is accounted for (blue) and when it is ignored (red). At higher frequencies it becomes increasingly important to account for wind acceleration.
The solar corona is threaded by magnetic fields that support a wide variety of magnetohydrodynamic (MHD) waves. These waves carry energy through the corona and are a powerful diagnostic: comparing how waves behave in models with what is observed lets us infer properties of the coronal plasma and magnetic field that are otherwise very difficult to measure.
My current work uses numerical simulations to model MHD waves in large-scale coronal structures such as helmet streamers, and compares them with observations from the Metis coronagraph on board Solar Orbiter (Kumar et al. 2026).
Cool, dense plasma can condense out of the hot coronae of stars and be held aloft by their magnetic fields, forming prominences. On rapidly rotating stars this material can be flung outwards as “slingshot prominences”, carrying mass and angular momentum away from the star; material that falls back towards the surface appears as coronal rain. Using 3D MHD simulations, I studied how this material forms, how often it is ejected, and how it might be detected, from radio emission to the material thought to shape the unusual light curves of scallop-shell stars (Daley-Yates et al. 2023; Daley-Yates & Jardine 2024; Daley-Yates et al. 2026).
Modern supercomputers are a vast tool for testing our understanding of the physical world, but they also present a challenging technical problem. Programs written for these machines need to be efficient, scalable, flexible and at the same time user friendly.
Terms such as exascale or massively parallel describe a code's ability to run on a very large number of threads while still executing efficiently, known as scalability. This is most commonly achieved with a hybrid parallelisation scheme, which reduces the volume of communication between distributed memory locations across a supercomputer by routing most of it through the shared memory within each node. Several frameworks exist for this; my work used Kokkos.
The image shown here is a rendering of an atmospheric convection simulation with a resolution of 50003 grid cells, where each snapshot is 5.2 TB of data (Daley-Yates et al. 2021). Simulations and data output on this scale are not possible without high-performance frameworks such as Kokkos and big-data management methods.
Throughout their lifetimes, stars and their planets form a closely bound, evolving system driven by many simultaneous physical processes. My research has aimed to understand the role magnetic fields play in shaping the environment around stars and planets, and how stars connect with their planets, the interstellar medium (ISM) and each other.
Magnetic fields are an innate property of stars and planets on all length scales, from small surface features to extended winds. The role they play in shaping the environment around stars and planets is central to understanding stellar and planetary formation and evolution, as well as large-scale structures such as the ISM and star clusters.
Much of this work concerned the winds and environments of main-sequence stars and close-in, Jupiter-type exoplanets. Using simulations as numerical experiments, I predicted observational signatures of stellar and planetary (co)evolution models to support current and future observational campaigns.
Radio emission from stars and planets is an extremely powerful diagnostic for testing theoretical models. Thermal emission from hot plasma and cyclotron emission from magnetically confined electrons occur in many stellar and planetary phenomena. From my simulation results I predict radio fluxes to test the models directly against observation.
Stars with masses above about 5 solar masses have winds driven by the intense radiation they produce. Massive stars can be tens of thousands of times more luminous than the Sun, and their winds can reach speeds of around 3000 km/s, much faster than the solar wind.
The star's magnetic field plays a central role, controlling the topology of the expanding wind. Its effect can be observed at radio wavelengths, giving insight into the dynamic environment close to the stellar surface. The image shown here is one of my simulations: the star is at the centre and the extended structures are iso-density contours. About 10% of massive stars are found to be detectably magnetic (Daley-Yates et al. 2019; ud-Doula et al. 2023).
Massive stars are also where elements are made. The extreme temperatures and pressures in their cores drive fusion up to iron, which has the highest binding energy per nucleon. Elements heavier than iron need more violent events: a massive star ends its life as a supernova, and the intense flux of neutrons released in such events builds heavy elements such as uranium through neutron capture. Elements on Earth heavier than iron were created in environments like these.
Closer to home, solar-type stars also possess magnetic fields. These can be as strong as those of their massive counterparts and are far more common: stars from the dimmest red dwarfs up to A-type stars have all been found to have magnetic fields to some extent.
My simulations of a solar-type star with an orbiting Jupiter-like planet magnetise both bodies with 1 G dipole fields, and initialise the winds of both using Parker's wind model. They show how material escaping the planet is channelled by the stellar magnetic field and can fall onto the star (Daley-Yates & Stevens 2019; Daley-Yates & Stevens 2018).
This list is generated automatically from NASA ADS and was last updated on 11 November 2026.