Near midplane scintillator-based fast ion loss detector on DIII-D

X Chen; R K Fisher; D C Pace; M García-Muñoz; J A Chavez; W W Heidbrink; M A Van Zeeland

doi:10.1063/1.4732063

Near midplane scintillator-based fast ion loss detector on DIII-D

Rev Sci Instrum. 2012 Oct;83(10):10D707. doi: 10.1063/1.4732063.

Authors

X Chen¹, R K Fisher, D C Pace, M García-Muñoz, J A Chavez, W W Heidbrink, M A Van Zeeland

Affiliation

¹ University of California-Irvine, USA. chenxi@fusion.gat.com

PMID: 23126881
DOI: 10.1063/1.4732063

Abstract

A new scintillator-based fast-ion loss detector (FILD) installed near the outer midplane of the plasma has been commissioned on DIII-D. This detector successfully measures coherent fast ion losses produced by fast-ion driven instabilities (≤500 kHz). Combined with the first FILD at ∼45° below the outer midplane [R. K. Fisher, et al., Rev. Sci. Instrum. 81, 10D307 (2010)], the two-detector system measures poloidal variation of losses. The phase space sensitivity of the new detector (gyroradius r(L) ∼ [1.5-8] cm and pitch angle α ∼ [35°-85°]) is calibrated using neutral beam first orbit loss measurements. Since fast ion losses are localized poloidally, having two FILDs at different poloidal locations allows for the study of losses over a wider range of plasma shapes and types of loss orbits.