Measurements of Alfvén Eigenmode stability in the 2021 JET DT campaign

We present measurements of Alfvén Eigenmode (AE) stability from the 2021 JET DT campaign. The AE Active Diagnostic resonates with stable AEs and measures total damping rates γ < 0, eigenfrequencies, and toroidal mode numbers [Fasoli 1995 PRL]. Of 2000+ datapoints in 200+ DT discharges, we highlight measurements that can be compared to reference D or T plasmas: stable edge EAEs during modulations of the NBI power and alpha population; simultaneous un/stable AEs in the search for nonlinear coupling of fast ions, turbulence, and AEs; and first-ever stability measurements during JET energetic particle afterglow experiments. We use the kinetic-MHD code NOVA-K to identify eigenmodes, assess stability, and evaluate the contribution, if any, from alphas.