# Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas

## Abstract

In this study, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell’s equations and the Fokker Planck equation self-consistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by Kennel-Engelmann diffusion, such as diffusion directions, wave polarizations, and H-theorem. The kinetic energy change (Wdot ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORIC-CQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.

- Authors:

- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
- Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
- XCEL Engineering, Oak Ridge, TN (United States)
- CompX, Del Mar, CA (United States)

- Publication Date:

- Research Org.:
- Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

- Sponsoring Org.:
- USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)

- OSTI Identifier:
- 1353216

- Alternate Identifier(s):
- OSTI ID: 1361850

- Grant/Contract Number:
- FC02-01ER54648; AC02-05CH11231; AC02-CH0911466

- Resource Type:
- Journal Article: Accepted Manuscript

- Journal Name:
- Physics of Plasmas

- Additional Journal Information:
- Journal Volume: 24; Journal Issue: 5; Journal ID: ISSN 1070-664X

- Publisher:
- American Institute of Physics (AIP)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; RF heating; tokamak; kinetic theory; cyclotron damping

### Citation Formats

```
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, and Bonoli, Paul.
```*Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas*. United States: N. p., 2017.
Web. doi:10.1063/1.4982060.

```
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, & Bonoli, Paul.
```*Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas*. United States. doi:10.1063/1.4982060.

```
Lee, Jungpyo, Wright, John, Bertelli, Nicola, Jaeger, Erwin F., Valeo, Ernest, Harvey, Robert, and Bonoli, Paul. Mon .
"Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas". United States.
doi:10.1063/1.4982060. https://www.osti.gov/servlets/purl/1353216.
```

```
@article{osti_1353216,
```

title = {Quasilinear diffusion coefficients in a finite Larmor radius expansion for ion cyclotron heated plasmas},

author = {Lee, Jungpyo and Wright, John and Bertelli, Nicola and Jaeger, Erwin F. and Valeo, Ernest and Harvey, Robert and Bonoli, Paul},

abstractNote = {In this study, a reduced model of quasilinear velocity diffusion by a small Larmor radius approximation is derived to couple the Maxwell’s equations and the Fokker Planck equation self-consistently for the ion cyclotron range of frequency waves in a tokamak. The reduced model ensures the important properties of the full model by Kennel-Engelmann diffusion, such as diffusion directions, wave polarizations, and H-theorem. The kinetic energy change (Wdot ) is used to derive the reduced model diffusion coefficients for the fundamental damping (n = 1) and the second harmonic damping (n = 2) to the lowest order of the finite Larmor radius expansion. The quasilinear diffusion coefficients are implemented in a coupled code (TORIC-CQL3D) with the equivalent reduced model of the dielectric tensor. We also present the simulations of the ITER minority heating scenario, in which the reduced model is verified within the allowable errors from the full model results.},

doi = {10.1063/1.4982060},

journal = {Physics of Plasmas},

number = 5,

volume = 24,

place = {United States},

year = {Mon Apr 24 00:00:00 EDT 2017},

month = {Mon Apr 24 00:00:00 EDT 2017}

}