Lin Shih
Postgraduate Researcher
University of York
Co-hort year: 2024 entry
I completed my undergraduate degree with a major in philosophy and a minor in physics, then continued my enthusiasm for physics by earning a master’s degree in physics at National Taiwan University in 2023. My background is in high energy physics experiments, where I worked on data analysis for the CMS experiment at CERN. I also participated in another project, a correlation study between earthquake events and anomalous radon emissions in Taiwan, as I hoped to identify precursors of disastrous earthquakes to prevent humans from catastrophe.
Driven by the global energy and climate crises, I started my journey into fusion plasma physics at National Cheng Kung University in Taiwan. In 2023, as the Taiwanese government initiated the FIRST project to build a spherical tokamak, I was fortunate to be one of the pioneers designing and simulating FIRST. My work involved calculating equilibrium with a high fraction of bootstrap current and high beta using VMEC in fixed boundary simulations and verifying MHD stability properties with DCON and TERPSICHORE. In the summer of 2024, I visited General Atomics in San Diego, USA, to complete the preliminary design of poloidal field coils using the free boundary equilibrium code EFIT. These experiences inspired me to pursue further studies in the UK, as I was captivated by the STEP project—a promising initiative to realise future fusion power plants—and was drawn to Fusion CDT.
My research in Fusion CDT will focus on modelling transport in the plasma edge using Hermes-3. Fusion reactions operate at extremely high temperatures, and as high temperature plasmas move outward to the edge through transport, they impose significant heat loads and fluxes on plasma-facing components. This can degrade fusion device performance and reduce longevity and durability. The divertor is designed to handle and mitigate these heat loads, and impurity gases such as argon and nitrogen are injected near the divertor target to cool the plasma through plasma-neutral interactions, which significantly reduces the heat loads on the divertor target. However, how the pumped impurity gas moves through the plasma edge and the influence of kinetic effects require a deeper understanding. We aim to answer these by modelling and simulating the impurity behaviour in the plasma edge. This helps optimise the operation in existing tokamak, such as the MAST-U, and provides guidance for the STEP, making the fusion energy reliable and sustainable.
