Vlasov simulations of electron acceleration by radio frequency heating near the upper hybrid layer
Najmi, A. and Eliasson, B. and Shao, X. and Milikh, G. and Sharma, A. S. and Papadopoulos, K. (2017) Vlasov simulations of electron acceleration by radio frequency heating near the upper hybrid layer. Physics of Plasmas, 24 (10). 102904. ISSN 1070-664X (https://doi.org/10.1063/1.4999768)
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Abstract
It is shown by using a combination of Vlasov and test particles simulations that the electron distribution function resulting from energization due to Upper Hybrid (UH) plasma turbulence depends critically on the closeness of the pump wave to the double resonance, defined as omega≈omega_UH≈n omega_ce where n is an integer. For pump frequencies, away from the double resonance the electron distribution function is very close to Maxwellian, while as the pump frequency approaches the double resonance it develops a high energy tail. The simulations show turbulence involving coupling between Lower Hybrid (LH) and UH waves, followed by excitation of Electron Bernstein (EB) modes. For the particular case of a pump with frequency between n=3 and n=4 the EB modes cover the range from the first to the 5th mode. The simulations show that when the injected wave frequency is between the 3rd and 4th electron cyclotron frequency, bulk electron heating occurs due to the interaction between the electrons and large amplitude EB waves, primarily on the first EB branch leading to an essentially thermal distribution. On the other hand, when the frequency is slightly above the 4th electron cyclotron harmonic, the resonant interaction is predominantly due to the UH branch and leads to a further acceleration of high-velocity electrons and a distribution function with a suprathermal tail of energetic electrons. The results are consistent with ionospheric experiments and relevant to the production of Artificial Ionospheric Plasma Layers.
ORCID iDs
Najmi, A., Eliasson, B. ORCID: https://orcid.org/0000-0001-6039-1574, Shao, X., Milikh, G., Sharma, A. S. and Papadopoulos, K.;-
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Item type: Article ID code: 61996 Dates: DateEvent26 October 2017Published8 October 2017AcceptedSubjects: Science > Physics Department: Faculty of Science > Physics Depositing user: Pure Administrator Date deposited: 11 Oct 2017 10:34 Last modified: 23 Nov 2024 01:10 Related URLs: URI: https://strathprints.strath.ac.uk/id/eprint/61996