March 2012

Conference Paper

Pellet interaction with runaway electrons

By:
James, A. N.; Hollmann, E. M.; Yu, J.H.; Austin, M. E.; Commaux, Nicolas J; Evans, T.E.; Humphrey, D. A.; Jernigan, Thomas C; Parks, P. B.; Putvinski, S.; Strait, E. J.; Tynan, G.; Wesley, J. C.
Journal Name:
Journal of Nuclear Materials
Page Number:
849-851
Volume:
415
Issue Number:
1
Publication Date:
March 2012
Conference Name:
19th International Conference on Plasma-Surface Interactions in Controlled Fusion Devices (PSI)
Conference Location:
San Diego, California, United States of America
Conference Sponsor:
Lawrence Livermore National Laboratory
View DOI Listing:
https://doi.org/10.1016/j.jnucmat.2011.01.135

Abstract

We describe results from recent experiments studying interaction of solid polystyrene pellets with a runaway electron current channel generated after cryogenic argon pellet rapid shutdown of DIII-D. Fast camera imaging shows the pellet trajectory and continuum emission from the subsequent explosion, with geometric calibration providing detailed explosion analysis and runaway energy. Electron cyclotron emission also occurs, associated with knock-on electrons broken free from the pellet by RE which then accelerate and runaway, and also with a short lived hot plasma blown off the pellet surface. In addition, we compare heating and explosion times from observations and a model of pellet heating and breakdown by runaway interaction. (C) 2011 Elsevier B.V. All rights reserved