First measurements of a scintillator based fast-ion loss detector near the ASDEX Upgrade divertor

J Gonzalez-Martin; J Ayllon-Guerola; M Garcia-Munoz; A Herrmann; P Leitenstern; P De Marne; S Zoletnik; A Kovacsik; J Galdon-Quiroga; J Rivero-Rodriguez; M Rodriguez-Ramos; L Sanchis-Sanchez; J Dominguez; ASDEX Upgrade Team; MST1 Team

doi:10.1063/1.5038968

First measurements of a scintillator based fast-ion loss detector near the ASDEX Upgrade divertor

Rev Sci Instrum. 2018 Oct;89(10):10I106. doi: 10.1063/1.5038968.

Authors

Affiliations

¹ Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, Spain.
² CNA (U. Sevilla, CSIC, J. de Andalucia), Seville, Spain.
³ Max-Planck-Institut für Plasmaphysik, Garching, Germany.
⁴ Wigner RCP, Budapest, Hungary.
⁵ Department of Mechanical and Manufacturing Engineering, University of Seville, C/Camino de los Descubrimientos s/n, Isla de la Cartuja, Seville, SpainCNA (U. Sevilla, CSIC, J. de Andalucia), Seville, SpainDepartment of Atomic, Molecular and Nuclear Physics, Faculty of Physics, University of Seville, 41012 Seville, SpainMax-Planck-Institut für Plasmaphysik, Garching, GermanyWigner RCP, Budapest, Hungary.

PMID: 30399966
DOI: 10.1063/1.5038968

Abstract

A new reciprocating scintillator based fast-ion loss detector has been installed a few centimeters above the outer divertor of the ASDEX Upgrade tokamak and between two of its lower Edge Localized Modes (ELM) mitigation coils. The detector head containing the scintillator screen, Faraday cup, calibration lamp, and collimator systems are installed on a motorized reciprocating system that can adjust its position via remote control in between plasma discharges. Orbit simulations are used to optimize the detector geometry and velocity-space coverage. The scintillator image is transferred to the light acquisition systems outside of the vacuum via a lens relay (embedded in a 3D-printed titanium holder) and an in-vacuum image guide. A charge coupled device camera, for high velocity-space resolution, and an 8 × 8 channel avalanche photo diode camera, for high temporal resolution (up to 2 MHz), are used as light acquisition systems. Initial results showing velocity-space of neutral beam injection prompt losses and fast-ion losses induced by a (2, 1) neoclassical tearing mode are presented.