Core tungsten radiation diagnostic calibration by small shell pellet injection in the DIII-D tokamak

E M Hollmann; N Commaux; D Shiraki; N Alexander; I Bykov; A L Moser; D Thomas; B S Victor

doi:10.1063/1.5005170

Core tungsten radiation diagnostic calibration by small shell pellet injection in the DIII-D tokamak

Rev Sci Instrum. 2017 Oct;88(10):103501. doi: 10.1063/1.5005170.

Authors

E M Hollmann¹, N Commaux², D Shiraki², N Alexander³, I Bykov¹, A L Moser³, D Thomas³, B S Victor⁴

Affiliations

¹ University of California-San Diego, 9500 Gilman Dr., La Jolla, California 92093-0417, USA.
² Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, USA.
³ General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA.
⁴ Lawrence Livermore National Laboratory, 7000 East Ave., Livermore, California 94550, USA.

PMID: 29092496
DOI: 10.1063/1.5005170

Abstract

Injection of small (outer diameter = 0.8 mm) plastic pellets carrying embedded smaller (10 μg) tungsten grains is used to check calibrations of core tungsten line radiation diagnostics in support of the 2016 tungsten ring campaign in the DIII-D tokamak. Observed total brightness (1 eV-10 keV) and soft x-ray (1 keV-10 keV) brightness are found to be reasonably well (<factor 2) predicted using existing calibration factors and rate calculations. Individual core (extreme ultra-violet/soft x-ray) tungsten line brightness appears to be somewhat less reliable (factor 2-4) for the prediction of core tungsten concentration.