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UKAEA-STEP-CP(24)022022
The UK’s Spherical Tokamak for Energy Production (STEP) reactor design program has recently taken the decision to use exclusively microwave-based heating and current drive (HCD) actuators for its reactor concepts. This is based on a detailed assessment considering all viable HCD concepts, covering the grid to plasma efficiency (), physics applica…
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UKAEA-STEP-CP(23)052022
The UK’s Spherical Tokamak for Energy Production (STEP) reactor design program is now exclusively investigating concepts using microwave-based heating and current drive (HCD) systems. Electron Bernstein Wave (EBW) HCD is a relatively immature technology compared to Electron Cyclotron (EC) HCD but is of interest due to the promise of high current…
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UKAEA-CCFE-PR(22)572022
The LOCUST GPU code has been applied to study the fast-ion transport caused by resonant magnetic perturbations in the high-performance Q = 10 ITER baseline scenario. The computational speed of the code is used calculate the impact of the ITER ELM-control-coil system on neutral beam heating efficiency, as well as producing detailed predictions o…
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UKAEA-CCFE-PR(21)192021
A novel high-performance computing algorithm, developed in response to the next generation of computational challenges associated with burning plasma regimes in ITER-scale tokamak devices, has been tested and is described herein. LOCUST-GPU 2 The Lorentz-Orbit Code for Use in Stellarators and Tokamaks (LOCUST) is designed for computationally scal…
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CCFE-PR(17)562017
The merging-compression method of plasma start-up in the Mega Amp Spherical Tokamak (MAST) involved the creation of two plasma tori with parallel currents, which merged at the vacuum vessel midplane due to their mutual attraction. Magnetic reconnection occurred in this process causing strong heating of both ions and electrons on millisecond timesca…
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CCFE-PR(17)462017
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 change in field topology, as the initially open magnetic field lines form closed flux surfaces (CFS) under the initiation of a plasma current. This change in field topology w…
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CCFE-PR(15)722015
The Synthetic Aperture Microwave Imaging (SAMI) diagnostic has conducted proof-of-principle 2D Doppler backscattering (DBS) experiments on MAST. SAMI actively probes the plasma edge using a wide ( 40° vertical and horizontal) and tuneable (10-35.5 GHz) beam. The Doppler backscattered signal is digitised in vector form using an array of eight Vival…
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CCFE-PR(15)1062015
Recent measurements of microwave and x-ray emission during edge localized mode (ELM) activity in tokamak plasmas provide a fresh perspective on ELM physics. It is evident that electron kinetics, which are not incorporated in standard (fluid) models for the instability that drives ELMs, play a key role in the new observations. These effects should b…
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2014
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 linearly polarised antennas. The array configuration has been optimised to achieve maximum synthetic aperture beam efficiency. The signals received by antennas are down-convert…
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2013
A novel microwave imaging system (SAMI) which utilises an array of phase sensitive antennas to synthesize an optical aperture has been designed and deployed on MAST. The system requires no optical components for focussing and yet is able to image up to half of the plasma surface simultaneously. All image formation is done in post processing and SAM…
Showing 1 - 10 of 14 UKAEA Paper Results