### Abstract

The electron drift velocity in argon with admixtures of up to 2% of nitrogen, hydrogen or oxygen is measured in a pulsed Townsend system for reduced electric fields ranging from 0.1 Td to 2.5 Td. The results are compared with those obtained by Monte Carlo simulations and from the solution of the electron Boltzmann equation using two different solution techniques: a multiterm method based on Legendre polynomial expansion of the angular dependence of the velocity distribution function and the S _{n} method applied to a density gradient expansion representation of the distribution function. An almost perfect agreement between the results of the three numerical methods and, in general, very good agreement between the experimental and the calculated results is obtained. Measurements in Ar-O _{2} mixtures were limited by electron attachment to oxygen molecules, which contributes to the measured drift velocity. As a result of this attachment contribution, the bulk drift velocity becomes larger than the flux drift velocity if attachment is more probable for electrons with energy below the mean value and smaller in the opposite case. Attachment also contributes to the negative differential conductivity observed in Ar-O _{2} mixtures.

Original language | English |
---|---|

Pages (from-to) | 489-498 |

Number of pages | 10 |

Journal | European Physical Journal D |

Volume | 65 |

Issue number | 3 |

DOIs | |

Publication status | Published - Dec 2011 |

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### ASJC Scopus subject areas

- Atomic and Molecular Physics, and Optics

### Cite this

_{2}, H

_{2}or O

_{2}on the electron drift velocity in argon: Experimental measurements and calculations.

*European Physical Journal D*,

*65*(3), 489-498. https://doi.org/10.1140/epjd/e2011-20296-7

**Effect of small admixtures of N _{2}, H _{2} or O _{2} on the electron drift velocity in argon : Experimental measurements and calculations.** / Stano, M.; Pinhão, N.; Loffhagen, D.; Kučera, M.; Donkó, Z.; Matejčík, Š.

Research output: Contribution to journal › Article

_{2}, H

_{2}or O

_{2}on the electron drift velocity in argon: Experimental measurements and calculations',

*European Physical Journal D*, vol. 65, no. 3, pp. 489-498. https://doi.org/10.1140/epjd/e2011-20296-7

_{2}, H

_{2}or O

_{2}on the electron drift velocity in argon: Experimental measurements and calculations. European Physical Journal D. 2011 Dec;65(3):489-498. https://doi.org/10.1140/epjd/e2011-20296-7

}

TY - JOUR

T1 - Effect of small admixtures of N 2, H 2 or O 2 on the electron drift velocity in argon

T2 - Experimental measurements and calculations

AU - Stano, M.

AU - Pinhão, N.

AU - Loffhagen, D.

AU - Kučera, M.

AU - Donkó, Z.

AU - Matejčík, Š

PY - 2011/12

Y1 - 2011/12

N2 - The electron drift velocity in argon with admixtures of up to 2% of nitrogen, hydrogen or oxygen is measured in a pulsed Townsend system for reduced electric fields ranging from 0.1 Td to 2.5 Td. The results are compared with those obtained by Monte Carlo simulations and from the solution of the electron Boltzmann equation using two different solution techniques: a multiterm method based on Legendre polynomial expansion of the angular dependence of the velocity distribution function and the S n method applied to a density gradient expansion representation of the distribution function. An almost perfect agreement between the results of the three numerical methods and, in general, very good agreement between the experimental and the calculated results is obtained. Measurements in Ar-O 2 mixtures were limited by electron attachment to oxygen molecules, which contributes to the measured drift velocity. As a result of this attachment contribution, the bulk drift velocity becomes larger than the flux drift velocity if attachment is more probable for electrons with energy below the mean value and smaller in the opposite case. Attachment also contributes to the negative differential conductivity observed in Ar-O 2 mixtures.

AB - The electron drift velocity in argon with admixtures of up to 2% of nitrogen, hydrogen or oxygen is measured in a pulsed Townsend system for reduced electric fields ranging from 0.1 Td to 2.5 Td. The results are compared with those obtained by Monte Carlo simulations and from the solution of the electron Boltzmann equation using two different solution techniques: a multiterm method based on Legendre polynomial expansion of the angular dependence of the velocity distribution function and the S n method applied to a density gradient expansion representation of the distribution function. An almost perfect agreement between the results of the three numerical methods and, in general, very good agreement between the experimental and the calculated results is obtained. Measurements in Ar-O 2 mixtures were limited by electron attachment to oxygen molecules, which contributes to the measured drift velocity. As a result of this attachment contribution, the bulk drift velocity becomes larger than the flux drift velocity if attachment is more probable for electrons with energy below the mean value and smaller in the opposite case. Attachment also contributes to the negative differential conductivity observed in Ar-O 2 mixtures.

UR - http://www.scopus.com/inward/record.url?scp=84856214034&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84856214034&partnerID=8YFLogxK

U2 - 10.1140/epjd/e2011-20296-7

DO - 10.1140/epjd/e2011-20296-7

M3 - Article

VL - 65

SP - 489

EP - 498

JO - Zeitschrift fur Physik D-Atoms Molecules and Clusters

JF - Zeitschrift fur Physik D-Atoms Molecules and Clusters

SN - 1434-6060

IS - 3

ER -