Fundamental Electromagnetic Emissions by a Weak Electron Beam in Solar Wind Plasmas with Density Fluctuations
نویسندگان
چکیده
Abstract The generation of Langmuir wave turbulence by a weak electron beam in randomly inhomogeneous plasma and its subsequent electromagnetic radiation are studied owing to two-dimensional particle-in-cell simulations conditions relevant type III solar radio bursts. essential impact random density fluctuations average levels few percents the background on characteristics at fundamental frequency ? p is shown. Not only nonlinear interactions but also processes waves’ transformations contribute such emissions. During relaxation, amount energy radiated with strongly exceeds that observed when homogeneous. fraction involved emissions saturates around 10 ?4 , i.e., one order magnitude above reached uniform. Moreover, whereas harmonic emission 2 dominates over during time evolution homogeneous plasma, dominant contains fluctuations, least several thousands periods before being overcome total begins saturate.
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ژورنال
عنوان ژورنال: The astrophysical journal
سال: 2022
ISSN: ['2041-8213', '2041-8205']
DOI: https://doi.org/10.3847/2041-8213/ac46a7