5 papers · 1 filter
On the effect of beating during nonlinear frequency chirping
Andreas Bierwage, Roscoe B. White, Vinícius N. Duarte
Spectral analyses of energetic particle (EP) driven bursts of MHD fluctuations in magnetically confined plasmas often exhibit multiple simultaneous chirps. While the superposition…
Microturbulence-mediated route for energetic ion transport and Alfvénic mode intermittency in tokamaks
Nikolai Gorelenkov, Vinicius Duarte
We report on a theoretical discovery of new regimes of Alfvén eigenmode (AE) induced fast ion transport in tokamak plasmas, where microturbulence plays the role of a mediator of fa…
Analytical nonlinear collisional dynamics of near-threshold eigenmodes
Vinicius Duarte, Nikolai Gorelenkov
A closed-form analytical solution is found for the nonlinear dynamics of isolated, near-threshold waves in the presence of strong scattering. The proposed solution can be useful in…
Resonance line broadened quasilinear (RBQ) model for fast ion distribution relaxation due to Alfvénic eigenmodes
Nikolai Gorelenkov, Vinicius Duarte, Mario Podesta +1
The burning plasma performance is limited by the confinement of the superalfvenic fusion products such as alpha particles and the auxiliary heating ions capable of exciting the Alf…
Study of the likelihood of Alfvénic mode bifurcation in NSTX and predictions for ITER baseline scenarios
Vinicius Duarte, Nikolai Gorelenkov, Mirjam Schneller +3
Rare Alfvénic wave transitions between fixed-frequency and chirping phases are identified in NSTX, where Alfvénic waves are normally observed to exhibit either chirping or avalanch…