Student Seminar -November 2019

Friday 8 November 2019, 2.00PM to 15:00

Speaker(s): Emma Hume, Liam Douglas-Mann & David West

Radiation Hydrodynamic Simulations of Laser-Solid Interactions

David West

The interaction between high intensity laser systems and solid targets is of great interest for a number of different systems such as ICF or ion beam generation. However, these interactions can evolve on very short timescales of the order of picoseconds, so to probe these types of interactions requires the use of simulations. One type of simulation technique involves the use of radiation hydrodynamic codes such as HYADES which solves a system of conservation equations: mass, momentum and energy; which is closed by an equation of state. This talk will introduce the use of radiation hydrodynamic codes for simulation and will thereafter discuss the results that have currently beenachieved.

Ultra-Intense Laser Interactions with Novel Nanowire Coated Targets

Emma Hume

The irradiation of solid targets with ultra-intense lasers leads to the creation of warm and hot dense matter, applicable to studies of laboratory astrophysics and inertial confinement fusion. Incident laser light will reflect at the so-called ‘critical density’ surface inside the target, presenting a limitation on direct laser heating of material. Accelerated ‘fast’ electrons from the laser-plasma interaction site are instead necessary for deeper heating and compression of the target. The generation of these fast electrons can be improved by using novel nanostructured targets.

In this talk an investigation into novel nanowire coated targets will be presented. An experiment testing the targets will be described, along with initial results from an optical transition radiation diagnostic. Further work will then be suggested following on from these preliminary results.

Dynamic Compression of Materials to Extreme Pressures: Modelling Compression Pathways

Liam Douglas-Mann

The behaviour of materials at extreme pressures in the high energy density regime is not well understood. Static techniques using conventional diamond anvil cells typically reach∼350 GPa at room temperature for most materials, but large planetary interiors are at pressures and temperatures that exceed these conditions by far. Dynamic compression techniques using high power lasers can reach extremely high pressures in a short period of time. Using a combination of loading techniques, the hard-to-reach regions of a material’s phase diagram can be explored. However, the effect of different compression pathways on material microstructure is not well characterised. Current work on modelling and comparing different compression pathways in molecular dynamics will be presented.

Location: Debye Lecture Theatre