Electrostatic thermal noise in a weakly ionized collisional plasma - Sorbonne Université Access content directly
Journal Articles Radio Science Year : 2017

Electrostatic thermal noise in a weakly ionized collisional plasma


Quasi-thermal noise (QTN) spectroscopy is a plasma diagnostic technique which enables precise measurements of local electron velocity distribution function moments. This technique is based on measurements and analysis of voltage fluctuations at the antenna terminals, induced by thermal motion of charged particles. In this work, we accommodate, for the first time, this technique to weakly ionized collisional plasmas. It turns out that the QTN spectrum is modified both at low frequencies, increasing the level of power spectrum, and around the plasma frequency, where collisions damp the plasma oscillations and therefore broaden and reduce the amplitude of so called " plasma peak, " while the spectrum at high frequencies is nearly unmodified compared to the collisionless case. Based on these results, we show that QTN spectroscopy enables independent measurements of the collision frequency, electron density, and temperature, provided the ratio of collision frequency to plasma frequency is í µí¼∕í µí¼ p ∼ 0.1. The method presented here can be used for precise estimation of plasma parameters in laboratory devices and unmagnetized ionospheres, while application in the ionosphere of Earth is possible but limited to small, low-frequency range due to magnetic field influence.
Fichier principal
Vignette du fichier
rds20501-1.pdf (554.65 Ko) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

hal-01446254 , version 1 (25-01-2017)



M. Martinović, A. Zaslavsky, M. Maksimović, S. Šegan. Electrostatic thermal noise in a weakly ionized collisional plasma. Radio Science, 2017, ⟨10.1002/2016RS006189⟩. ⟨hal-01446254⟩
144 View
175 Download



Gmail Facebook X LinkedIn More