numerical modeling of electron cascade processes leading to breakdown in argon gas

Authors

  • bassam ghazolin tishreen university

Abstract

This research presents a general numerical modeling of electron cascade processes leading to breakdown in argon gas. The model succeed to interpret the breakdown phenomenon in argon gas over pressure range from 1.368x102 torr to 2.35x103 torr irradiated with the second harmonic of the Nd:galss laser of wave length is equal  0.53 mm and pulse duration is 15 ns. The output of the computer program enabled us to obtained some relations for the electron energy distribution function (EEDF) and its parameters. 

                 The EEDF gradually decreases up 12 eV (first excitation limit) followed by a sharp decrease resulting in a tail at e = 21 eV ending with a very small value of the EEDF ~1 to 10. This gradual decrease can be explained due to the fast energy gain in elastic processes associated with the laser filed which causes an accumulation of energy to values exceeding the excitation (or ionization) threshold of the gas atoms, eventually causing their excitation or ionization. This result clarifies that during the first half of the laser flash losses has no contribution to the values of the EEDF. The only parameter which affect these values is the laser intensity. At the end of the laser flash, however, a noticeable drop of the EEDF is observed when recombination losses are present.

 

Published

2022-09-15

How to Cite

1.
غزولين ب. numerical modeling of electron cascade processes leading to breakdown in argon gas. TUJ-BA [Internet]. 2022Sep.15 [cited 2024May3];44(4):21-3. Available from: https://journal.tishreen.edu.sy/index.php/bassnc/article/view/12283