UKAEA Papers

Showing 21 - 30 of 236 UKAEA Paper Results
2021
UKAEA-CCFE-PR(21)77

The optimum conditions for access to and sustainment of H-mode plasmas and their expected plasma parameters in the Pre-Fusion Power Operation 1 (PFPO-1) phase of the ITER Research Plan, where the additional plasma heating will be provided by 20 MW of Electron Cyclotron Heating (ECH), are assessed in order to identify key open R&D issues. The as…

Preprint Published
2021
UKAEA-CCFE-PR(21)78

Alfvén eigenmode (AE) instabilities driven by alpha-particles have been observed in D-3He fusion experiments on the Joint European Torus (JET) with the ITER-like wall (ILW). For the efficient generation of fusion alpha-particles from D-3He fusion reaction, the 3‑ion radio frequency (RF) scenario was used t…

Preprint
2021
UKAEA-CCFE-PR(21)77

The optimum conditions for access and sustainment of H-mode plasmas and their expected plasma parameters in the Pre-Fusion Operation 1 (PFPO-1) phase of the ITER Research Plan, where the additional plasma heating will be provided by 20 MW of Electron Cyclotron Heating (ECH), are assessed. The assessment is performed on the basis of empirical and…

Preprint Published
2021
UKAEA-CCFE-PR(21)76

We present the first parallel electron transport results obtained using the newly developed 1D transport code SOL-KiT. In order to properly predict divertor heat loads it is of key importance to develop a thorough understanding of discrepancies between different parallel transport modelling approaches. With the capability to self-consistently sw…

Preprint Published
2021
UKAEA-CCFE-PR(21)73

During bursty MHD events, transient ion cyclotron emission (ICE) is observed from deuterium plasmas in the Large Helical Device (LHD) heliotron-stellarator. Unusually, the frequencies of the successive ICE spectral peaks are not close to integer multiples of the local cyclotron frequency of an energetic ion population in the likely emitting regi…

Preprint
2021
UKAEA-CCFE-PR(21)71

In this paper, the pixelated phase mask (PPM) method of interferometry is applied to coherence imag-ing (CI) — a family of passive, narrowband spectro-polarimetric imaging techniques for diagnosing plasmas. Compared to designs using a linear phase mask, PPM is more compact, rugged and has a higher spatial resolution (averaged across both image…

Preprint
2021
UKAEA-CCFE-CP(21)10

This paper shows experimental results from the TCV tokamak that indicate plasma-molecule interactions involving D+2 and possibly D− play an important role as sinks of energy (through hydrogenic radiation as well as dissociation) and particles during divertor detachment if low target temperatures (< 3 eV) are achieved. Bot…

Preprint Published
2021
UKAEA-CCFE-CP(21)08

The pedestal plays an important role in determining the confinement in tokamak H-mode plasmas. However, the steep pressure gradients in this transport barrier also lead to edge localized modes (ELMs) [1]. There is good understanding of the pedestal in type I ELM regimes [2], however, type I ELMs are known to damage plasma facing components and f…

Preprint Purchase
2021
UKAEA-CCFE-CP(21)07

The disruption mitigation system at ITER will include four shattered pellet injectors (SPI), which will be dedicated to the mitigation of electro-magnetic loads (EML), thermal loads and the avoidance and suppression of runaway electrons. Recently the JETILW was equipped with an SPI with a wide capability. Specifically: pellet diameter d = [4.57, 8.…

Preprint
2021
UKAEA-CCFE-CP(21)06

In this work we provide experimental insights into the impact of plasma-molecule interactions on divertor detachment by applying new spectroscopic analysis techniques to the hydrogen Balmer line series to investigate how both atom and plasma-molecule interactions impact particle balance. Our analysis on a representative L-mode TCV density ramp dis…

Preprint Purchase
The published version of this paper is currently under embargo and will be available on 16/02/2023