Observations of Anisotropic Ion Temperature during RF Heating in the NSTX Edge

Technical Report · Mon May 19 04:00:00 EDT 2003

DOI:https://doi.org/10.2172/814015· OSTI ID:814015

Biewer, T M ^[1]; Bell, R E; Darrow, D S; Phillips, C K; Wilson, J R

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1. Princeton Plasma Physics Laboratory

A new spectroscopic diagnostic on the National Spherical Torus Experiment (NSTX) measures the velocity distribution of ions in the plasma edge with both poloidal and toroidal views. An anisotropic ion temperature is measured during the presence of high power HHFW RF heating in He plasmas, with the poloidal T(sub)i roughly twice the toroidal T(sub)i. Moreover, the measured spectral distribution suggests that two populations have temperatures of 500 eV and 50 eV with rotation velocities of -50 km/s and -10 km/s, respectively. This bi-modal distribution is observed in both the toroidal and poloidal views (in both He II and C III ions), and is well correlated with the period of RF power application to the plasma. The temperature of the edge ions is observed to increase with the applied RF power, which was scanned between 0 and 4.3MW. The ion heating mechanism from HHFW RF power has not yet been identified.

• Research Organization: Princeton Plasma Physics Lab., NJ (US)
• Sponsoring Organization: USDOE Office of Science (SC) (US)
• DOE Contract Number: AC02-76CH03073
• OSTI ID: 814015
• Report Number(s): PPPL-3813
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DIAGNOSTICS
DISTRIBUTION
EDGE PLASMA
HEATING
ION HEATING
ION TEMPERATURE
PLASMA
ROTATION
VELOCITY