Abstract
Constraints are imposed on whistler generation in solar-flare loops. It is shown that the effective generation of whistlers is possible only under specific conditions: when the anisotropy of nonthermal electrons is sufficiently strong, the magnetic field is relatively weak (less than 200 G), or the plasma density is relatively high (more than 1010 cm–3). Otherwise, whistlers in flare loops will be strongly absorbed by the nonthermal electrons accelerated in the flare.
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REFERENCES
Bespalov, P.A. and Trakhtengerts, V.Yu., Al’fvenovskie mazery (Alfvén Masers), IPFAN, 1986.
Charikov, Yu.E. and Shabalin, A.N., Hard X-ray generation in the turbulent plasma of solar flares, Geomagn. Aeron. (Engl. Transl.), 2016, vol. 56, no. 8, pp. 1068–1074.
Filatov, L.V. and Melnikov, V.F., Influence of whistler turbulence on fast electron distribution and their microwave emission in a flare loop, Geomagn. Aeron. (Engl. Transl.), 2017, vol. 57, no. 8, pp. 1001–1008.
Hamilton, R.J. and Petrosian, V., Stochastic acceleration of electrons and effects of collisions in solar flares, Astrophys. J., 1992, vol. 398, no. 10, pp. 350–358.
Kaplan, S.A. and Tsytovich, V.N., Plasma Astrophysics, Oxford: Pergamon, 1973.
Kennel, C.F. and Petschek, H.E., Limit on stably trapped particle fluxes, J. Geophys. Res., 1966, vol. 71, no. 1, pp. 1–28.
Kudryavtsev, I.V. and Charikov, Yu.E., Kinetics of fast electrons in ion-acoustic waves in the turbulent plasma of solar flares, Sov. Astron., 1991, vol. 35, no. 4, pp. 409–414.
Melnikov, V.F., Particle acceleration and capture in impulsive and gradual bursts: Results of analysis of microwave and hard X-ray emissions, Radiophys. Quantum Electron., 1994, vol. 37, no. 7, pp. 557–568.
Melrose, D.B., Resonant scattering of particles and second phase acceleration in the solar corona, Sol. Phys., 1974, vol. 37, no. 4, pp. 353–365.
Miller, J.A., Electron acceleration in solar flares by fast mode waves: quasi-linear theory and pitch-angle scattering, Astrophys. J., 1997, vol. 491, no. 2, pp. 939–951.
Musset, S., Kontar, E.P., and Vilmer, N., Diffusive transport of energetic electrons in the solar corona: X-ray and radio diagnostics, Astron. Astrophys., 2018, vol. 610, id A6.
Stepanov, A.V. and Tsap, Y.T., Electron-wistler interaction in coronal loops and radiation signatures, Sol. Phys., 2002, vol. 211, pp. 135–154.
Wentzel, D.G., Condition for “storage” of energetic particles in the solar corona, Astrophys. J., 1976, vol. 208, pp. 595–608.
Yasnov, L.V. and Chernov, G.P., Alternative models of zebra patterns in the event on June 21, 2011, Sol. Phys., 2020, vol. 295, id 13. https://doi.org/10.1007/s11207-020-1585-5
Funding
This work was supported by the Russian Foundation for Basic Research (project nos. 18-02-00856, and 17-52-80064, and the program CAS 2016VWA044).
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Translated by M. Samokhina
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Melnikov, V.F., Filatov, L.V. Conditions for Whistler Generation by Nonthermal Electrons in Flare Loops. Geomagn. Aeron. 60, 1126–1131 (2020). https://doi.org/10.1134/S0016793220080150
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DOI: https://doi.org/10.1134/S0016793220080150