# Radiation temperature of non-equilibrium plasmas

## Abstract

In fusion devices measurements of the radiation temperature T{sub r} ({omega}, k) near the electron cyclotron frequency {omega}{sub C} and the second harmonic 2{omega}{sub C} in directions nearly perpendicular to the confining magnetic field B (i.e., k {approx} k {perpendicular}) serve to map out the electron temperature profiles T{sub e}(r,t). For optically thick plasma at thermodynamic equilibrium T{sub r} = T{sub e}. However, there is increasing experimental evidence for the presence of non-equilibrium electron distributions (such as a drifting Maxwellian with appreciable values of the streaming parameter {omicron} = v{sub d}/v{sub t}, a bi- Maxwellian, and anisotropic Maxwellian with T {perpendicular} {ne} T {parallel}, etc.,) in tokamak plasmas, especially in the presence of radio-frequency heating. Here, we examine (both non-relativistically and relativistically) the dependence of T{sub r} on {omicron}, T{perpendicular}/T{parallel}, T{sub h}/T{sub b}, n{sub h}/n{sub b}etc., where n{sub b}, n{sub h}, T{sub b}, T{sub h} are the densities and temperatures, respectively, of the bulk and the hot components of the bi-Maxwellian plasma. Our bi-Maxwellian results predict that the ratio T{sub r}/T{sub e} is a very sensitive function of the ratios n{sub h}/n{sub b} and T{sub h}/T{sub b}. Further, these relativistic and non-relativistic results satisfy the well-known limit c {yields} {infinity}more »

- Authors:

- Publication Date:

- Research Org.:
- Princeton Univ., NJ (United States). Plasma Physics Lab.

- Sponsoring Org.:
- USDOE; USDOE, Washington, DC (United States)

- OSTI Identifier:
- 5457072

- Report Number(s):
- PPPL-2782

ON: DE91016217; TRN: 91-022198

- DOE Contract Number:
- AC02-76CH03073

- Resource Type:
- Technical Report

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTROMAGNETIC RADIATION; TEMPERATURE DISTRIBUTION; NON-EQUILIBRIUM PLASMA; BOLTZMANN EQUATION; DISTRIBUTION FUNCTIONS; ECR HEATING; ELECTRON TEMPERATURE; MAGNETIC FIELDS; TEMPERATURE MEASUREMENT; DIFFERENTIAL EQUATIONS; EQUATIONS; FUNCTIONS; HEATING; HIGH-FREQUENCY HEATING; PARTIAL DIFFERENTIAL EQUATIONS; PLASMA; PLASMA HEATING; RADIATIONS; 700103* - Fusion Energy- Plasma Research- Kinetics

### Citation Formats

```
Arunasalam, V.
```*Radiation temperature of non-equilibrium plasmas*. United States: N. p., 1991.
Web. doi:10.2172/5457072.

```
Arunasalam, V.
```*Radiation temperature of non-equilibrium plasmas*. United States. doi:10.2172/5457072.

```
Arunasalam, V. Mon .
"Radiation temperature of non-equilibrium plasmas". United States. doi:10.2172/5457072. https://www.osti.gov/servlets/purl/5457072.
```

```
@article{osti_5457072,
```

title = {Radiation temperature of non-equilibrium plasmas},

author = {Arunasalam, V},

abstractNote = {In fusion devices measurements of the radiation temperature T{sub r} ({omega}, k) near the electron cyclotron frequency {omega}{sub C} and the second harmonic 2{omega}{sub C} in directions nearly perpendicular to the confining magnetic field B (i.e., k {approx} k {perpendicular}) serve to map out the electron temperature profiles T{sub e}(r,t). For optically thick plasma at thermodynamic equilibrium T{sub r} = T{sub e}. However, there is increasing experimental evidence for the presence of non-equilibrium electron distributions (such as a drifting Maxwellian with appreciable values of the streaming parameter {omicron} = v{sub d}/v{sub t}, a bi- Maxwellian, and anisotropic Maxwellian with T {perpendicular} {ne} T {parallel}, etc.,) in tokamak plasmas, especially in the presence of radio-frequency heating. Here, we examine (both non-relativistically and relativistically) the dependence of T{sub r} on {omicron}, T{perpendicular}/T{parallel}, T{sub h}/T{sub b}, n{sub h}/n{sub b}etc., where n{sub b}, n{sub h}, T{sub b}, T{sub h} are the densities and temperatures, respectively, of the bulk and the hot components of the bi-Maxwellian plasma. Our bi-Maxwellian results predict that the ratio T{sub r}/T{sub e} is a very sensitive function of the ratios n{sub h}/n{sub b} and T{sub h}/T{sub b}. Further, these relativistic and non-relativistic results satisfy the well-known limit c {yields} {infinity} correspondence principle'', showing that the intensity of the emission and absorption line is independent of the line broadening mechanism. 44 refs., 2 figs.},

doi = {10.2172/5457072},

journal = {},

number = ,

volume = ,

place = {United States},

year = {1991},

month = {7}

}