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Title: Self-regulated oscillation of transport and topology of magnetic islands in toroidal plasmas

The coupling between the transport and magnetic topology is an important issue because the structure of magnetic islands, embedded in a toroidal equilibrium field, depends on the nature of the transport at the edge of the islands. Measurements of modulated heat pulse propagation in the DIII-D tokamak have revealed the existence of self-regulated oscillations in the radial energy transport into magnetic islands that are indicative of bifurcations in the island structure and transport near the q = 2 surface. Large amplitude heat pulses are seen in one state followed by small amplitude pulses later in the discharge resulting in a repeating cycle of island states. These two states are interpreted as a bifurcation of magnetic island with high and low heat pulse accessibility. In conclusion, this report describes the discovery of a bifurcation in the coupled dynamics between the transport and topology of magnetic islands in tokamak plasmas.
 [1] ;  [1] ;  [2] ;  [3] ;  [4] ;  [5] ;  [1] ;  [1] ;  [3] ;  [1]
  1. National Institute for Fusion Science, Gifu (Japan)
  2. General Atomics, San Diego, CA (United States)
  3. Kyushu Univ., Kasuga (Japan)
  4. Univ. of Texas, Austin, TX (United States)
  5. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Grant/Contract Number:
FC02-04ER54698; FG03-97ER54415; AC05-00OR22725; 15H02336; 21224014; 23360414
Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 5; Journal ID: ISSN 2045-2322
Nature Publishing Group
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); US Department of Energy
Sponsoring Org:
Japan Society for the Promotion of Science (JSPS); USDOE Office of Science (SC)
Country of Publication:
United States
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; magnetically confined plasmas; particle astrophysics
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1259712; OSTI ID: 1351976