Dr Daniel Kennedy

Introduction

I am a theoretical plasma physicist at the UK Atomic Energy Authority (UKAEA) at Culham, where I lead research on core plasma turbulence for MAST-U, the UK’s flagship fusion experiment, and contribute to the development of STEP, the UK's prototype fusion power plant. I also lecture in theoretical plasma physics at the University's Rudolf Peierls Centre for Theoretical Physics.

I came to Oxford from a state sixth-form college in Bury, Greater Manchester, and studied Mathematics, followed by Mathematical and Theoretical Physics, at Merton College. I completed my PhD at the Max Planck Institute for Plasma Physics in Greifswald, Germany, working on the kinetic theory of electron-positron plasmas, before returning to Oxfordshire in 2021 to join UKAEA. I joined St Peter's as College Lecturer in Physics in October 2026.

Teaching

At St Peter's, I teach first-year physicists, giving tutorials in the Mathematical Methods papers (CP3 and CP4) and contributing to collections and admissions alongside Professor Foot and Dr Coulton.

In the Department of Physics, I lecture on the graduate courses Collisionless Plasma Physics and Advanced Topics in Plasma Physics. I also supervise four DPhil students working in theoretical plasma physics.

Research

Fusion reactors confine plasma at temperatures exceeding one hundred million degrees using magnetic fields. The plasma is turbulent, and that turbulence leaks heat out of the machine faster than almost any other process. Predicting this transport, and finding ways to reduce it, is a central problem in my research. I use gyrokinetic theory, the kinetic theory of charged particles in strong magnetic fields, together with some of the largest plasma simulations run on UK and European supercomputers.

I am particularly interested in spherical tokamaks, from MAST Upgrade (MAST-U) at Culham to next-generation reactors such as STEP. In these machines, the plasma pressure can become large enough to distort the confining magnetic field, giving rise to electromagnetic instabilities known as kinetic ballooning modes. My recent work characterises these modes, shows how the turbulence they drive can switch abruptly between low- and high-transport states, and identifies routes to "second stability", a regime in which increasing pressure can become stabilising rather than destabilising.

I also retain broader interests in electron-positron plasmas and in turbulence in geophysical and astrophysical fluids.

Selected Publications

On the transition to large fluxes and access to second stability in gyrokinetic simulations of electromagnetic turbulence in STEP

DOI: 10.1088/1741-4326/ae9323

On the importance of parallel magnetic-field fluctuations for electromagnetic instabilities in STEP

DOI: 10.1088/1741-4326/ad58f3

Electromagnetic gyrokinetic instabilities in STEP

DOI: 10.1088/1741-4326/ad08e7

Coulomb collisions in strongly anisotropic plasmas I. Cyclotron cooling in electron-ion plasmas

DOI: 10.1017/S0022377820001622

Coulomb collisions in strongly anisotropic plasmas II. Cyclotron cooling in laboratory pair plasmas

DOI: 10.1017/S0022377820001233