@article{7477,
  author = {B. J. Tobias and C.W. Domier and N C Luhmann Jr. and J. E. Boom and I.G.J. Classen and A. J. H. Donne and G. Yun and H. K. Park and R. M. Nazikian},
  title = {Sawtooth Precursor Oscillations on DIII-D},
  abstract = {The sawtooth oscillation, observed in tokamak plasmas with a central safety factor of less than unity, is a periodic disruptive instability characterized by a slow ramping of central plasma density and temperature, followed by a fast relaxation resulting in flattening of both profiles. Elongated neutral-beam-heated discharges on the DIII-D tokamak exhibit multiple precursor oscillations with mode number m/n = 1/1. The dominant m/n = 1/1 mode oscillates at the plasma rotation frequency. A downshifted mode also appears early in the sawtooth ramp. A normalization of electron cyclotron emission imaging data that removes the contribution of slow electron temperature profile evolution reveals that both modes are consistent with an underlying quasi-interchange plasma displacement.
},
  year = {2011},
  journal = {IEEE Transactions on Plasma Science},
  volume = {39},
  number = {11},
  pages = {3022-3023},
  month = {Nov},
  isbn = {0093-3813},
  doi = {10.1109/TPS.2011.2157535},
  note = {ISI Document Delivery No.: 884CVTimes Cited: 0Cited Reference Count: 3Part 1SI},
  language = {English},
}