Abstract
[1] An electrostatic parallel particle-in-cell (EPPIC) code that allows for particle beam injections and multiple boundary conditions is used to investigate the beam-plasma interaction and its manifestations in the incoherent scatter (IS) spectrum. Specifically, the code is used to investigate anomalous enhancements in the ion acoustic line through the destabilization of the plasma by injection (or precipitation) of low-energy electron beams. This enhancement of the ion acoustic line is a form of IS distortion commonly observed in the vicinity of auroral arcs called the naturally enhanced ion-acoustic line (NEIAL). Simulations confirm the parametric decay of Langmuir waves as a plausible mechanism, assuming a mechanism for the formation of dense low-energy (<10 eV) electron beams in the ionosphere. The spectral distortions are similar at aspect angles as large as ±15° from the beam direction. Simulations also show that the first Langmuir harmonic can have a power intensity higher than that of the ion acoustic line of a thermal plasma. Conditions which would allow the detection of Langmuir harmonics with existing incoherent scatter radars are discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.