Formation and Stability of Impurity "snakes" in Tokamak Plasmas

Technical Report · Mon Jan 28 00:00:00 EST 2013

DOI:https://doi.org/10.2172/1062401· OSTI ID:1062401

L Delgado-Aparicio, et al

New observations of the formation and dynamics of long-lived impurity-induced helical "snake" modes in tokamak plasmas have recently been carried-out on Alcator C-Mod. The snakes form as an asymmetry in the impurity ion density that undergoes a seamless transition from a small helically displaced density to a large crescent-shaped helical structure inside q < 1, with a regularly sawtoothing core. The observations show that the conditions for the formation and persistence of a snake cannot be explained by plasma pressure alone. Instead, many features arise naturally from nonlinear interactions in a 3D MHD model that separately evolves the plasma density and temperature

• Research Organization: Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-ACO2-09CH11466
• OSTI ID: 1062401
• Report Number(s): PPPL-4847
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
TokamaksTomography