@inproceedings{465df0d130ba489a8cec6e09c74706be,
title = "Measurements of critical gradient behavior of fast-ion transport from Alfv{\'e}n eigenmodes for predictive model development",
abstract = "Experiments in the DIII-D tokamak show that many overlapping small-amplitude Alfv{\'e}n eigenmodes (AEs) cause fast-ion transport that is consistent with the critical gradient paradigm. Measurements indicate a sudden increase in fast-ion transport in the presence of many simultaneous AEs at a threshold in neutral beam power corresponding to a threshold for orbit stochasticity [1]. The threshold varies in fast-ion phase space and is well above the AE linear stability threshold, meaning that some AEs can be tolerated before performance-degrading transport occurs. Above threshold, transport becomes stiff, resulting in virtually unchanged fast-ion density profiles despite increased beam drive. These studies are being used to develop a validated, predictive transport model that can efficiently calculate AE-induced transport and the resulting fast-ion profile over a wide parameter regime in order to design optimal fusion reactor scenarios that avoid undesirable AE-transport.",
author = "Collins, \{C. S.\} and Heidbrink, \{W. W.\} and M. Podest{\`a} and White, \{R. B.\} and Kramer, \{G. J.\} and Pace, \{D. C.\} and Petty, \{C. C.\} and L. Stagner and \{Van Zeeland\}, \{M. A.\} and Zhu, \{Y. B.\}",
note = "Publisher Copyright: {\textcopyright} 2017 IOP Publishing Ltd.; 44th European Physical Society Conference on Plasma Physics, EPS 2017 ; Conference date: 26-06-2017 Through 30-06-2017",
year = "2017",
language = "English (US)",
isbn = "9781510849303",
series = "44th EPS Conference on Plasma Physics, EPS 2017",
publisher = "European Physical Society (EPS)",
editor = "A. Bret and M. Fajardo and E. Westerhof and A. Melzer and B. Dromey and C. Riconda",
booktitle = "44th EPS Conference on Plasma Physics, EPS 2017",
}