https://doi.org/10.1140/epjp/s13360-020-00699-9
Regular Article
Ion source terms effect on collisional plasma sheath characteristics with non-extensively distributed electrons
1
Physics Department, Faculty of Science and Techniques, Abdelmalek Essaadi University, Al-Hoceima, Morocco
2
Laboratory of Physics of Matter and Radiations, Physics Department, Faculty of Science, University Mohammed I, Oujda, Morocco
Received:
25
December
2019
Accepted:
17
August
2020
Published online:
28
August
2020
A one-dimensional fluid model of an unmagnetized collisional plasma sheath consisting of q-non-extensive electrons and singly charged positive ions with finite temperature is developed and presented. The ions are described by the fluid model, which is based on the continuity and momentum equations of ions, while the electrons are considered obeying non-extensive distribution according to the Tsallis statistics. In this work, different ion source terms are used in order to compare their contribution. The modified Bohm sheath criterion is determined for different source terms to specify the ion velocity at sheath entrance. The model equations are solved numerically in the plasma-wall transition region. The effect of ion source terms on the collisional electropositive plasma sheath characteristics such as ion and electron density, electric potential, ion velocity, sheath width and space charge is investigated. The influence of the ionization frequency parameter on the sheath behavior has also been studied. The results obtained show a strong impact of ion source terms on the plasma sheath structure. It is also shown that the ion source terms effect increases significantly when the ionization frequency parameter increases.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2020
