15 citations · 68 across the 15 of their papers we have counts for
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First Experimental Evidence of Helicon Current Drive
J. B. Lestz, R. I. Pinsker, B. Van Compernolle +10
Helicon current drive is an attractive solution for driving current to sustain steady state tokamak operation in reactor conditions. Dedicated DIII-D experiments have been conducte…
Resonant Pitch-Angle Scattering Of Runaway-Electrons by Externally-launched Helicon Waves in the DIII-D Tokamak
Hari Choudhury, Jeffrey Lestz, Carlos Paz-Soldan +12
Resonant wave-particle interactions between externally launched helicon waves (also known as whistler waves) and runaway electrons (REs) have been demonstrated on the DIII-D tokama…
Robust Control of ECH Deposition Profiles on DIII-D
A. Rothstein, H. J. Farre-Kaga, K. Yasoda +5
Electron Cyclotron Heating (ECH) is a key actuator in DIII-D and future tokamaks that provides auxiliary heating, localized current drive for scenario development and MHD stability…
Predictive capabilities of the integrated modeling TRANSP code for tokamak plasmas
A. Y. Pankin, J. Breslau, M. V. Gorelenkova +7
This paper expands on the TRANSP description given in [Computer Physics Communications 312 (2025) 109611] by describing recent progress in TRANSP's predictive functionality and emp…
Effects of Tungsten Radiative Cooling on Impurity, Heat and Momentum Transport in DIII-D Plasmas
A. Tema Biwole, T. Odstrčil, X. Litaudon +21
A first-of-its-kind experiment was conducted in the DIII-D tokamak under WEST similarity constraints on plasma shape and core parameters. This work presents a detailed transport st…
Sensitivities of time-dependent temperature profile predictions for NSTX with the Multi-Mode Model
J. B. Lestz, G. Avdeeva, S. M. Kaye +5
The Multi-Mode Model (MMM) for turbulent transport was applied to a large set of well-analyzed discharges from the National Spherical Torus Experiment (NSTX) in order to evaluate i…
Assessing time-dependent temperature profile predictions using reduced transport models for high performing NSTX plasmas
J. B. Lestz, G. Avdeeva, T. F. Neiser +6
Time-dependent, predictive simulations were performed with the 1.5D tokamak integrated modeling code TRANSP on a large set of well-analyzed, high performing discharges from the Nat…
First Demonstration of Resonant Pitch-Angle Scattering of Relativistic Electrons by Externally-Launched Helicon Waves
H. Choudhury, A. Battey, C. Paz-Soldan +12
Helicon waves satisfying the normal wave-particle cyclotron resonance are observed to limit the growth and maximum energy of relativistic electrons (REs) in low-density Ohmic DIII-…
Analytic quasi-steady evolution of a marginally unstable wave in the presence of drag and scattering
J. B. Lestz, V. N. Duarte
The 1D bump-on-tail problem is studied in order to determine the influence of drag on quasi-steady solutions near marginal stability () when effective collisions ar…
Hybrid simulations of sub-cyclotron compressional and global Alfvén Eigenmode stability in spherical tokamaks
J. B. Lestz, E. V. Belova, N. N. Gorelenkov
A comprehensive numerical study has been conducted in order to investigate the stability of beam-driven, sub-cyclotron frequency compressional (CAE) and global (GAE) Alfvén Eigenmo…
Shifting and splitting of resonance lines due to dynamical friction in plasmas
V. N. Duarte, J. B. Lestz, N. N. Gorelenkov +1
A quasilinear plasma transport theory that incorporates Fokker-Planck dynamical friction (drag) and pitch angle scattering is self-consistently derived from first principles for an…
Theory and Simulations of Compressional and Global Alfven Eigenmode Stability in Spherical Tokamaks
J. B. Lestz
Neutral-beam-driven, sub-cyclotron compressional (CAE) and global (GAE) \Alfven eigenmodes are routinely excited in spherical tokamaks such as NSTX(-U) and MAST, have been observed…
Analytic stability boundaries for compressional and global Alfvén eigenmodes driven by fast ions. II. Interaction via Landau resonance
J. B. Lestz, N. N. Gorelenkov, E. V. Belova +2
Conditions for net fast ion drive are derived for beam-driven, co-propagating, sub-cyclotron compressional (CAE) and global (GAE) Alfvén eigenmodes driven by the Landau resonance w…
Analytic stability boundaries for compressional and global Alfvén eigenmodes driven by fast ions. I. Interaction via ordinary and anomalous cyclotron resonances
J. B. Lestz, N. N. Gorelenkov, E. V. Belova +2
Conditions for net fast ion drive are derived for beam-driven, sub-cyclotron compressional (CAE) and global (GAE) Alfvén eigenmodes, such as those routinely observed in spherical t…
Energetic-particle-modified global Alfvén eigenmodes
J. B. Lestz, E. V. Belova, N. N. Gorelenkov
Fully self-consistent hybrid MHD/particle simulations reveal strong energetic particle modifications to sub-cyclotron global Alfvén eigenmodes (GAE) in low-aspect ratio, NSTX-like…