44 citations · 101 across the 14 of their papers we have counts for
14 papers
Simulation and analysis of a high-k electron scale turbulence diagnostic for MAST-U
David C. Speirs, Juan Ruiz-Ruiz, Maurizio Giacomin +7
Plasma turbulence on disparate spatial and temporal scales plays a key role in defining the level of confinement achievable in tokamaks, with the development of reduced numerical m…
Machine learning characterisation of Alfvénic and sub-Alfvénic chirping and correlation with fast ion loss at NSTX
Benjamin J. Q. Woods, Vinícius N. Duarte, Eric D. Fredrickson +3
Abrupt large events in the Alfvénic and sub-Alfvénic frequency bands in tokamaks are typically correlated with increased fast ion loss. Here, machine learning is used to speed up t…
The deteriorating effect of plasma density fluctuations on microwave beam quality
Alf Köhn, Max E. Austin, Michael W. Brookman +13
Turbulent plasma edge density fluctuations can broaden a traversing microwave beam degrading its quality. This can be a problem for scenarios relying on a high spatial localization…
Positivity-preserving scheme for two-dimensional advection-diffusion equations including mixed derivatives
Erasmus J. du Toit, Martin R. O'Brien, Roddy G. L. Vann
In this work, we propose a positivity-preserving scheme for solving two-dimensional advection-diffusion equations including mixed derivative terms, in order to improve the accuracy…
Stochastic effects on phase-space holes and clumps in kinetic systems near marginal stability
Benjamin J. Q. Woods, Vinicius N. Duarte, Anthony P. De-Gol +2
The creation and subsequent evolution of marginally-unstable modes have been observed in a wide range of fusion devices. This behaviour has been successfully explained, for a singl…
Resolving ECRH deposition broadening due to edge turbulence in DIII-D by heat deposition measurement
Michael W Brookman, Matthew B Thomas, Jarrod Leddy +7
Interaction between microwave power, used for local heating and mode control, and density fluctuations can produce a broadening of the injected beam, as confirmed in experiment and…
Resolving ECRH deposition broadening due to edge turbulence in DIII-D by 3D full-wave simulations
Matthew B Thomas, Michael W Brookman, Max E Austin +5
Edge plasma density fluctuations are shown to have a significant effect on the electron cyclotron resonance heating (ECRH) beam in the DIII-D tokamak. Experimental measurements of…
Kinetic study of plasma current start-up under EBW power in tokamak plasmas
Erasmus J. du Toit, Martin R. O'Brien, Roddy G. L. Vann
Tokamak plasma current start-up assisted by Electron Bernstein waves (EBW) has been demonstrated successfully in a number of experiments. The dynamic start-up phase involves a chan…
A kinetic study of microwave start-up of tokamak plasmas
Erasmus J. du Toit, Martin R. O'Brien, Roddy G. L. Vann
A kinetic model for studying the time evolution of the distribution function for microwave start-up is presented. The model for the distribution function is two dimensional in mome…
Overview of recent physics results from MAST
A Kirk, J Adamek, RJ Akers +160
New results from MAST are presented that focus on validating models in order to extrapolate to future devices. Measurements during start-up experiments have shown how the bulk ion…
Observations of 2D Doppler backscattering on MAST
D. A. Thomas, K. J. Brunner, S. J. Freethy +3
The Synthetic Aperture Microwave Imaging (SAMI) diagnostic has conducted proof-of-principle 2D Doppler backscattering (DBS) experiments on MAST. SAMI actively probes the plasma edg…
Electron kinetics inferred from observations of microwave bursts during edge localised modes in the Mega-Amp Spherical Tokamak
S. J. Freethy, K. G. McClements, S. C. Chapman +5
Recent measurements of microwave and X-ray emission during edge localised mode (ELM) activity in tokamak plasmas provide a fresh perspective on ELM physics. It is evident that elec…
Propagation in 3D of microwaves through density perturbations
T. R. N. Williams, A. Köhn, M. R. O'Brien +1
Simulations using 3D and 2D full-wave codes have shown that edge filaments in tokamak plasmas can significantly affect the propagation of microwaves across a broad frequency spectr…
Synthetic aperture microwave imaging with active probing for fusion plasma diagnostics
Vladimir F. Shevchenko, Roddy G. L. Vann, Simon J. Freethy +1
A Synthetic Aperture Microwave Imaging (SAMI) system has been designed and built to obtain 2-D images at several frequencies from fusion plasmas. SAMI uses a phased array of linear…