# Effect of the q-nonextensive electron velocity distribution on a magnetized plasma sheath

## Abstract

In this work, a sheath model has been developed to investigate the effect of the q-nonextensive electron velocity distribution on the different characteristics of a magnetized plasma. By using Segdeev potential method, a modified Bohm criterion for a magnetized plasma with the nonextensive electron velocity distribution is derived. The sheath model is then used to analyze numerically the sheath structure under different q, the parameter quantifying the nonextensivity degree of the system. The results show that as the q-parameter decreases, the floating potential becomes more negative. The sheath length increases at the lower values of the q-parameter due to the increase in the electron population at the high-energy tail of the distribution function. As q-parameter decreases, the effective temperature of the electrons increases which results in a more extended plasma sheath. The ion velocity and density profiles for the different nonextensivity degrees of the system reflect the gyro-motion of the ions in the presence of the magnetic field. Furthermore, the results coincide with those given by the Maxwellian electron distribution function, when q tends to 1.

- Authors:

- Laser and Plasma Research Institute, Shahid Beheshti University, Tehran 1983963113 (Iran, Islamic Republic of)

- Publication Date:

- OSTI Identifier:
- 22303761

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BOHM CRITERION; DISTRIBUTION FUNCTIONS; ELECTRONS; MAGNETIC FIELDS; PLASMA SHEATH; VELOCITY

### Citation Formats

```
Safa, N. Navab, E-mail: n-navabsafa@sbu.ac.ir, Ghomi, H., and Niknam, A. R.
```*Effect of the q-nonextensive electron velocity distribution on a magnetized plasma sheath*. United States: N. p., 2014.
Web. doi:10.1063/1.4892966.

```
Safa, N. Navab, E-mail: n-navabsafa@sbu.ac.ir, Ghomi, H., & Niknam, A. R.
```*Effect of the q-nonextensive electron velocity distribution on a magnetized plasma sheath*. United States. doi:10.1063/1.4892966.

```
Safa, N. Navab, E-mail: n-navabsafa@sbu.ac.ir, Ghomi, H., and Niknam, A. R. Fri .
"Effect of the q-nonextensive electron velocity distribution on a magnetized plasma sheath". United States.
doi:10.1063/1.4892966.
```

```
@article{osti_22303761,
```

title = {Effect of the q-nonextensive electron velocity distribution on a magnetized plasma sheath},

author = {Safa, N. Navab, E-mail: n-navabsafa@sbu.ac.ir and Ghomi, H. and Niknam, A. R.},

abstractNote = {In this work, a sheath model has been developed to investigate the effect of the q-nonextensive electron velocity distribution on the different characteristics of a magnetized plasma. By using Segdeev potential method, a modified Bohm criterion for a magnetized plasma with the nonextensive electron velocity distribution is derived. The sheath model is then used to analyze numerically the sheath structure under different q, the parameter quantifying the nonextensivity degree of the system. The results show that as the q-parameter decreases, the floating potential becomes more negative. The sheath length increases at the lower values of the q-parameter due to the increase in the electron population at the high-energy tail of the distribution function. As q-parameter decreases, the effective temperature of the electrons increases which results in a more extended plasma sheath. The ion velocity and density profiles for the different nonextensivity degrees of the system reflect the gyro-motion of the ions in the presence of the magnetic field. Furthermore, the results coincide with those given by the Maxwellian electron distribution function, when q tends to 1.},

doi = {10.1063/1.4892966},

journal = {Physics of Plasmas},

number = 8,

volume = 21,

place = {United States},

year = {Fri Aug 15 00:00:00 EDT 2014},

month = {Fri Aug 15 00:00:00 EDT 2014}

}