UKAEA Journals

Showing 1 - 4 of 4 Journals Results
2021
UKAEA-CCFE-PR(21)09
"Density dependence of ion cyclotron emission from deuterium plasmas in the Large Helical Device"

B. C. G. Reman R. O. Dendy T. Akiyama S. C. Chapman J. W. S. Cook H. Igami S. Inagaki K. Saito M.H. Kim S.G. Thatipamula G. S. Yun

Ion cyclotron emission (ICE) driven by perpendicular neutral beam-injected (NBI) deuterons, together with the distinctive ICE driven by tangential NBI, have been observed from heliotron-stellarator plasmas in the Large Helical Device (LHD). Radio frequency radiation in the lower hybrid range has also been observed, with frequency dependent on plasm…

Preprint
2019
UKAEA-CCFE-PR(19)08
"Interpretation of suprathermal emission at deuteron cyclotron harmonics from deuterium plasmas heated by neutral beam injection in the KSTAR tokamak"

B Chapman R O Dendy S C Chapman K G McClements G S Yun S G Thatipamula M H Kim

Intense bursts of suprathermal radiation, with spectral peaks at frequencies corresponding to the deuteron cyclotron frequency in the outer midplane edge region, are often detected from deuterium plasmas in the KSTAR tokamak that are heated by tangential neutral beam injection (NBI) of deuterons at 100 keV. Identifying the physical process by wh…

Preprint Published
2018
UKAEA-CCFE-PR(18)11
"Nonlinear wave interactions generate high-harmonic cyclotron emission from fusion-born protons during a KSTAR ELM crash"

B. Chapman R. O. Dendy S. C. Chapman K. G. McClements G. S. Yun S. G. Thatipamula M. H. Kim

Chirping observed in ion cyclotron emission (ICE) from the KSTAR tokamak at sequential proton harmonics in the range 200 to 500 MHz has recently been interpreted (B. Chapman et al., Nucl. Fusion 57, 124004 (2017)) as due to fast, sub-microsecond, evolution of the local deuterium plasma density. This density evolution changes the plasma environment …

Preprint Published
2017
CCFE-PR(17)04
"Sub-microsecond Temporal Evolution of Edge Density During Edge Localized Modes in KSTAR Tokamak Plasmas Inferred from Ion Cyclotron Emission"

B. Chapman R.O. Dendy K.G. McClements S.C. Chapman G.S. Yun S.G. Thatipamula M.H. Kim

Ion cyclotron emission (ICE) is detected during edge localised modes (ELMs) in the KSTAR tokamak at harmonics of the proton cyclotron frequency in the outer plasma edge. The emission typically chirps downward (occasionally upward) during ELM crashes, and is driven by confined 3MeV fusion-born protons that have large drift excursions from the plasma…

Preprint Published