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arXiv · 2304.06814

Two-stream instability with a growth rate insensitive to collisions in a dissipative plasma jet

Yi Zhou·Paul M. Bellan
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Abstract

The two-stream instability (Buneman instability) is traditionally derived as a collisionless instability with the presumption that collisions inhibit this instability. We show here via a combination of a collisional two-fluid model and associated experimental observations made in the Caltech plasma jet experiment, that in fact, a low frequency mode of the two-stream instability is indifferent to collisions. Despite the collision frequency greatly exceeding the growth rate of the instability, the instability can still cause an exponential growth of electron velocity and a rapid depletion of particle density. High collisionality nevertheless has an important effect as it enables the development of a double layer when the cross-section of the plasma jet is constricted by a kink-instigated Rayleigh-Taylor instability.

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Yi Zhou, Paul M. Bellan. 2023-04-13. Two-stream instability with a growth rate insensitive to collisions in a dissipative plasma jet. https://doi.org/10.1063/5.0146806

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