The production and confinement of runaway electrons with impurity killer pellets in DIII-D
- General Atomics, San Diego, CA (United States)
- Univ. of California, San Diego, La Jolla, CA (United States); and others
Prompt runaway electron bursts, generated by rapidly cooling DIII-D plasmas with argon killer pellets, are used to test a recent knock-on avalanche theory describing the growth of multi-MeV runaway electron currents during disruptions in tokamaks. Runaway current amplitudes, observed during some but not all DIII-D current quenches, are consistent with growth rates predicted by the theory assuming a pre-current quench runaway electron density of approximately 10{sup 15} m{sup {minus}3}. Argon killer pellet modeling yields runaway densities of between 10{sup 15}--10{sup 16} m{sup {minus}3} in these discharges. Although knock-on avalanching appears to agree rather well with the measurements, relatively small avalanche amplification factors combined with uncertainties in the spatial distribution of pellet mass and cooling rates make it difficult to unambiguously confirm the proposed theory with existing data.
- Research Organization:
- General Atomics, San Diego, CA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of California, San Diego, La Jolla, CA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research, Washington, DC (United States)
- DOE Contract Number:
- AC03-89ER51114; AC05-96OR22464; FG03-95ER54294
- OSTI ID:
- 319809
- Report Number(s):
- GA-A22976; CONF-981064-; ON: DE99001958; TRN: 99:003969
- Resource Relation:
- Conference: 17. IAEA fusion energy conference, Yokohama (Japan), 19-24 Oct 1998; Other Information: PBD: Dec 1998
- Country of Publication:
- United States
- Language:
- English
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