Two-dimensional time evolution of beam-plasma instability in the presence of binary collisions

¹ Instituto de Física, Universidade Federal do Rio Grande do Sul, 91501-970 Porto Alegre, RS, Brazil
² Institute for Physical Science & Technology, University of Maryland, College Park, MD 20742, USA
³ School of Space Research, Kyung Hee University, Yongin, 446-701 Gyeonggi, South Korea
⁴ School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK

Received: 29 August 2015
Accepted: 21 November 2015

Abstract

Energetic electrons produced during solar flares are known to be responsible for generating solar type III radio bursts. The radio emission is a byproduct of Langmuir wave generation via beam-plasma interaction and nonlinear wave-wave and wave-particle interaction processes. In addition to type III radio bursts, electrons traveling downwards toward the chromosphere lead to the hard X-ray emission via electron-ion collisions. Recently, the role of Langmuir waves on the X-ray-producing electrons has been identified as important, because Langmuir waves may alter the electron distribution, thereby affecting the X-ray profile. Both Coulomb collisions and wave-particle interactions lead electrons to scattering and energy exchange that necessitates considering the two-dimensional (2D) problem in velocity space. The present paper investigates the influence of binary collisions on the beam-plasma instability development in 2D in order to elucidate the nonlinear dynamics of Langmuir waves and binary collisions. The significance of the present findings in the context of solar physics is discussed.