UKAEA Journals

Showing 1 - 9 of 9 Journals Results
2016
CCFE-PR(16)61

In the last three years, magnetic reconnection research in the MAST spherical tokamak achieved major progress by use of new 32 chord ion Doppler tomography, 130 channel YAG and 300 channel Ruby Thomson scattering diagnostics. In addition to the previously achieved high power plasma heating during merging, detailed full temperature profile measureme…

Preprint Published
2016
CCFE-PR(16)31

This paper describes a recent advances in merging/reconnection experiments in MAST, namely tomographic ion Doppler spectroscopy capability from 2013 which solves the problem of the absence of ion temperature profile measurement during the solenoid-less startup. Providing 32 channel line-integrated spectra from 0.25m< rtangential <1.1m are con…

Preprint
2015
CCFE-PR(15)71

Electron and ion heating characteristics during merging reconnection startup on the MAST spherical tokamak have been revealed in detail using 130 channel YAG- and 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron de…

Preprint Published
2015
CCFE-PR(15)112

The Small Negative Ion Facility (SNIF) at CCFE has been undergoing continuous development and enhancement to both improve operational reliability and increase diagnostic capability. SNIF uses a CW 13.56MHz, 5kW RF driven volume source with a 30kV triode accelerator. Improvement and characterisation work includes: • Installation of a new “L” t…

Preprint Published
2014

Using the recently-installed Fast-Ion Deuterium Alpha (FIDA) spectrometer, the effects of low-frequency (20 - 50 kHz) chirping energetic particle modes with toroidal mode number n = 1 on the NBI-driven fast-ion population in MAST plasmas are considered. Results from the FIDA diagnostic are presented and discussed in the light of the present theoret…

Published
2009

This paper reports on a modern implementation of a Langmuir probe method that was first proposed in the 1950’s. The system directly measures the first and second derivative of the I-V characteristic and determines the EEDF. This probe offers many advantages over existing systems that rely on numerical differentiating and data smoothing techniques…

Published
2008

Measurements have been made of the emittance plot of a partly neutralized positive ion beamlet, using a slit, a polymer target, and an infrared camera. This thermographic approach is intrinsically linear and absolute since the properties of the target are known and approximately independent of temperature. It is sufficiently sensitive that only one…

Published
2007

Determining d 2 I/dV 2 from a traditional Langmuir probe trace using numerical techniques is inherently noisy and generally yields poor results. We have developed a Langmuir probe system based on a method first used in the 1950's by Boyd and Twiddy [1]. The system measures the 2nd derivative directly. This paper presents results from the d…

Published
2006

The Kamaboko III negative ion source, which was designed and built by JAERI, Naka, Japan, is a model 25% in linear dimensions of the reference design ion source for the International Thermonuclear Experimental Reactor ITER neutral beam injectors. The ion source is a magnetic multi-pole, arc discharge, source with 12 tungsten filaments. Cesium is ad…

Published