@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 = {11/2011},
  isbn = {0093-3813},
  doi = {10.1109/TPS.2011.2157535},
  note = {ISI Document Delivery No.: 884CVTimes Cited: 0Cited Reference Count: 3Part 1SI},
  language = {English},
}