Isotopic mass and fast ion effects in JET alpha heating plasmas

Experiments to detect alpha heating were performed in TFTR (1994) [1] and in JET (DTE1 1997) [2]. Observations of alpha heating were reported. Hydrogenic isotopic mass effects were seen in TFTR, but were assumed to be negligible in JET although unexpectedly high T$_i$ was seen in the DT plasmas. A reanalysis [3] showed strong correlation of core T$_e$ and T$_i$ with isotopic mass A, and with the time delays of significant sawteeth. Here effects of fast ions are studied. Beam ion pressure is also correlated with suppression of significant sawteeth, but is not correlated as strongly with the core T$_e$ and T$_i$. Beam and alpha ion effects on confinement and heating are reported. $^a$See the Appendix of F. Romanelli et al., Proceedings of the 25th IAEA Fusion Energy Conference 2014, Saint Petersburg, Russia. [1] G.Taylor, {\it et al.,}, Phys. Review Lett. {\bf 76} 2722 (1996. [2] Thomas, {\it et al.,} Phys. Review Lett. {\bf 80} 5548 (1998). [3] R.V.Budny, Nucl. Fusion {\bf 56} 036013 (2016).