Lab Astrophysics and High Energy Densities

PhD project for October 2026
Supervised by Dr Brian Appelbe, b.appelbe07@ic.ac.uk  & Prof Jeremy Chittenden, j.chittenden@ic.ac.uk 

The astrophysical production sites which facilitate nucleosynthesis in nature are bodies of extreme density, temperature and pressure. Neutron induced reactions, in particular the slow and rapid neutron capture processes, are the main drivers of nucleosynthesis in stars, supernovae and neutron star mergers. The extreme temperature and density conditions cause significant populations of the nuclei undergoing neutron capture reactions to exist in nuclear excited states, often referred to as isomers. Reaction cross sections can vary substantially for different states of nuclear excitation, and so accurate prediction of nucleosynthesis rates requires accurate knowledge of excitation rates (isomer production) at a given temperature and density.

The National Ignition Facility (NIF) carries out Inertial Confinement Fusion (ICF) experiments in which plasmas are compressed to reach temperatures and densities similar to those found in the centre of stars (temperatures of ~10 keV, densities of ~10^4 kg m^-3). These experiments can provide an ideal platform for studying isomer production and neutron capture reactions in hot, dense plasmas. At these conditions the plasmas produce large amounts of fast neutrons and excite significant numbers of nuclei into isomeric states. However, accurate theoretical and computational models for the isomer production in these experiments do not exist. Developing such models will be essential for designing ICF experiments to address outstanding questions in nuclear astrophysics. This is a new field of research, made possible by recent experimental breakthroughs at the NIF, where the required plasma conditions and neutron fluxes can now be created in the laboratory. This PhD project seeks to use nuclear and plasma theory to develop a computational model of isomer production that will be coupled to computational models describing the hydrodynamic evolution of the plasma in ICF experiments, thereby providing accurate predictions for the rates of neutron capture on excited states occurring in hot plasmas. The project will involve collaboration with scientists at a number of institutions, including at the NIF. The project will be based within the Centre for Inertial Fusion Studies at Imperial College.

Funding - TBD

PhD project for October 2026

Supervised by
Prof. Sergey Lebedev, s.lebedev@ic.ac.uk Dr Lee Suttle, l.suttle10@ic.ac.uk Prof. Simon Bland sn.bland@ic.ac.uk 

High Energy Density Physics (HEDP) explores the behaviour of matter and radiation under extreme conditions of temperature, pressure, and magnetic field—conditions comparable to those found in astrophysical environments and schemes for inertial confinement fusion (ICF). This PhD project will take place on Blackett Laboratory’s in-house 1-MA MAGPIE generator, which uses a 500-ns, 1-TW pulse of electrical energy to produce and accelerate plasma flows to supersonic velocities, whilst carrying dynamically significant magnetic fields. 

The scope of the project will be to isolate and investigate fundamental processes in the domain of magnetized, HEDP environments, such as magnetized transport, shock formation, reconnection, and plasma instabilities relevant to ICF, as they evolve into turbulence. These studies will rely on the use and continued development of MAGPIE’s world-leading suite of plasma diagnostics, using techniques such as Thomson-scattering, Faraday rotation imaging, Zeeman polarisation spectroscopy and refractometric imaging amongst others.