Student Placement - Plasma Systems

Understanding plasma transport in the edge of tokamak reactors is of crucial importance because the edge plasma both poses boundary conditions for the core confined region, and provides the transition from the hot (potentially burning) core and the material surface of the vacuum vessel. Specifically, the condition of the plasma directly in front divertor targets poses engineering constraints on future reactors. In ST40, we are trying to understand the transport of the edge plasmas from upstream to the target in a high field spherical tokamak, in order to make reliable predictions for future reactor design. 

Langmuir probes (LP) are a type of plasma diagnostics that dates its origins all the way to the beginning of plasma physics, and is still one of the best diagnostics that we have today for cold, tenuous plasmas. It is widely applied in both space plasmas (installed on satellites), and in tokamak edge plasmas. On ST40, two sets of 6 Langmuir probes have been newly commissioned. Preliminary data is readily available from the last ST40 campaign, with new data available starting late Spring 2024. This project will focus on detailed analysis of LP data to produce plasma temperature, density, floating potential, and grounding current profile for both the upper and lower divertors. A comparison of classical interpretation with non-linear curve fitting against Fourier-space spectral analysis will be performed. Results will aim to shed light on the bulk plasma properties as well as electron energy distributions and turbulence fluctuations in ST40 edge plasmas. 

This is an experimental project focused on data analysis, with no hardware component. There will be opportunities for participating in the experimental campaign, supporting control-room data interpretation. Prior experience with computer programming is preferred. 

In this role, you will: 

• Work in a team of plasma physicists, and gain exposure to plasma diagnostics, experimental analysis, and theory/ modelling 
• Learn the relevant fundamental plasma physics, including Debye shielding and plasma fluid / kinetic transport 

• Write and run python scripts to analysis Langmuir Probe data 
• Participate in ST40 experimental campaign 

Requirements

• University level electromagnetism required 
• Statistical physics preferred 
• Programming experience preferred 
• Oral and written communication skills 
• Passion to learn new skills and problem-solve essential 

Benefits

• Fusion Industry experience.
• Be part of a dynamic team and collaborate with experts in field.
• 10 days holiday.
• Competitive pay.