Joe Allen

University Of York

I am a PhD student in the SAMI research group, supervised by Dr Roddy Vann.

My research project title is “Microwave imaging of the tokamak plasma edge”, specifically focusing on the SAMI (Synthetic Aperture Microwave Imaging) diagnostic device, currently installed on NSTX-U in Princeton. With its 8 antennae, affording a wide field of view, SAMI can measure plasma microwave emissions actively or passively at a sampling rate of 250 MHz. I will analyse plasma microwave activity in order to measure the elusive edge current density, along with extending innovative pitch angle measurements from SAMI data and looking at consequences of turbulence in the outer plasma.

Edge localised mode (ELM) control is vital for the longevity of next generation tokamaks, necessitating collection of detailed edge pressure gradient and current density data. Edge pressure gradients can be attained with existing methods, however edge current density remains difficult to measure directly, making values determined from SAMI data important for the future of ELM mitigation.