TY - JOUR
T1 - Tomographic reconstructions of the fast-ion phase space using imaging neutral particle analyser measurements
AU - ASDEX-Upgrade Team
AU - Rueda-Rueda, J.
AU - Garcia-Munoz, M.
AU - Viezzer, E.
AU - Schneider, P. A.
AU - Oyola, P.
AU - Galdon-Quiroga, J.
AU - Salewski, M.
AU - Schmidt, B. S.
AU - Garcia-Dominguez, J.
N1 - Publisher Copyright:
© 2024 The Author(s). Published by IOP Publishing Ltd.
PY - 2024/6
Y1 - 2024/6
N2 - In this paper we demonstrate how the inversion, in energy and major radius (E, R) coordinates, of imaging neutral particle analyser (INPA) measurements can be used to obtain the fast-ion distribution. The INPA is most sensitive to passing ions with energies in the range (20-150) keV and pitches near 0.5 in the core and 0.7 near the plasma edge. Inversion of synthetic signals, via 0th-order Tikhonov and Elastic Net regularization, were performed to demonstrate the capability of recovering the ground truth fast-ion 2D phase-space distribution resolved in major radius and energy, even in the presence of moderate noise levels (10%). Finally, we apply our method to measure the 2D phase-space distribution in an MHD quiescent plasma at ASDEX Upgrade and find good agreement with the slowing down fast-ion distribution predicted by TRANSP.
AB - In this paper we demonstrate how the inversion, in energy and major radius (E, R) coordinates, of imaging neutral particle analyser (INPA) measurements can be used to obtain the fast-ion distribution. The INPA is most sensitive to passing ions with energies in the range (20-150) keV and pitches near 0.5 in the core and 0.7 near the plasma edge. Inversion of synthetic signals, via 0th-order Tikhonov and Elastic Net regularization, were performed to demonstrate the capability of recovering the ground truth fast-ion 2D phase-space distribution resolved in major radius and energy, even in the presence of moderate noise levels (10%). Finally, we apply our method to measure the 2D phase-space distribution in an MHD quiescent plasma at ASDEX Upgrade and find good agreement with the slowing down fast-ion distribution predicted by TRANSP.
KW - fast-ion diagnosis
KW - neutral particle analyser
KW - scintillator diagnostics
KW - tomographic inversions
UR - https://www.scopus.com/pages/publications/85193021582
UR - https://www.scopus.com/inward/citedby.url?scp=85193021582&partnerID=8YFLogxK
U2 - 10.1088/1361-6587/ad4486
DO - 10.1088/1361-6587/ad4486
M3 - Article
AN - SCOPUS:85193021582
SN - 0741-3335
VL - 66
JO - Plasma Physics and Controlled Fusion
JF - Plasma Physics and Controlled Fusion
IS - 6
M1 - 065025
ER -