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Microwave Emission of a Flare Loop in the Presence of Whistler Turbulence

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Abstract

The mutual influence of whistler turbulence and fast nonthermal electrons injected into a coronal flare loop is considered. For the loop, аs the inhomogeneous and nonstationary magnetic trap, the kinetic one-dimensional equation is solved in the Fokker–Planck approximation, which takes into account the scattering of fast electrons on whistlers. It is shown that whistlers can both be generated by fast electrons and be damped on them at a certain density of the background plasma and magnetic-field strength. The reverse action of the formed whistler turbulence significantly changes the characteristics of the time, pitch-angle, and energy distributions of electrons. In particular, it leads to breaks in the energy spectrum of nonthermal electrons. As a consequence, this also results in variations of the relevant characteristics of gyrosynchrotron emission of the flare loop.

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Funding

This work was supported by the Russian Foundation for Basic Research, projects no. 18-02-00856, and 17-52-80064, and the program CAS 2016VWA044.

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Authors and Affiliations

  1. Nizhny Novgorod State University of Architecture and Civil Engineering, 603600, Nizhny Novgorod, Russia

    L. V. Filatov

  2. Pulkovo Observatory, Russian Academy of Sciences, 196140, St. Petersburg, Russia

    V. F. Melnikov

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  1. L. V. Filatov
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  2. V. F. Melnikov
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Correspondence to L. V. Filatov.

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Translated by M. Samokhina

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Filatov, L.V., Melnikov, V.F. Microwave Emission of a Flare Loop in the Presence of Whistler Turbulence. Geomagn. Aeron. 60, 1137–1145 (2020). https://doi.org/10.1134/S0016793220080083

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