Abstract
The influence of magnetic turbulence on the hard X-ray brightness distribution in magnetic loops during solar flares was studied. An analysis was perfomed based on the solution of the kinetic equation for relativistic electrons, in which the regular energy loss, Coulomb scattering, magnetic reflection, and the effect of the reverse current and magnetic turbulence are taken into account. It was shown that scattering by magnetic inhomogeneities with parameter η = δB/B = 10–3 results in an increase in hard X-ray brightness at loop footpoints when the distribution of accelerated electrons is isotropic and mostly in the loop coronal part if the electron source is anisotropic. The influence of magnetic turbulence is absent at δB/B ≤ 10–5.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Aschwanden, M.J., Brown, J.C., and Kontar, E.P., Chromospheric height and density measurements in a solar flare observed with RHESSI-II. Data analysis, Sol. Phys., 2002, vol. 210, pp. 383–405.
Bai, T. and Ramaty, R., Backscatter, anisotropy, and polarization of solar hard X-rays, Astrophys. J., 1978, vol. 219, pp. 705–726.
Charikov, Yu.E., Melnikov, V.F., and Kudryavtsev, I.V., Intensity and polarization of the hard X-ray radiation of solar flares at the top and footpoints of a magnetic loop, Geomagn. Aeron. (Engl. Transl.), 2012, vol. 52, pp. 1021–1031.
Charikov, Yu.E., Shabalin, A.N., and Kudryavtsev, I.V., Hard X-ray emission of accelerated electrons in a loopstructure of the magnetic field during solar flares, Nauchno-Tekh. Vedomosti SPbGPU. Fiz-Mat. Nauki, 2013, no. 4–1, pp. 154–165.
Gluckstern, R.L. and Hull, M.H., Polarization dependence of the integrated bremsstrahlung cross section, Phys. Rev., 1953, vol. 90, no. 6, pp. 1030–1035.
Hamilton, R.J., Lu, E.T., and Petrosian, V., Numerical solution of the time-dependent kinetic equation for electrons in magnetized plasma, Astrophys. J., 1990, vol. 354, pp. 726–734.
Kontar, E.P., Bian, N.H., Emslie, A.G., and Vilmer, N., Turbulent pitch-angle scattering and diffusive transport of hard-X-ray producing electrons in flaring coronal loops, Astrophys. J., 2014, vol. 780, no. 2, 176.
Lee, M.A., Coupled hydromagnetic wave excitation and ion acceleration upstream of the Earth’s bow shock, J. Geophys. Res., 1982, vol. 87, no. A7, pp. 5063–5083.
Lin, R.P., Dennis, B.R., Hurford, G.J., et al., The Reuven Ramaty Righ-Energy Solar Spectroscopic Imager (RHESSI), Sol. Phys., 2002, vol. 210, no. 3.
McClements, K.G., The simultaneous effects of collisions, reverse currents and magnetic trapping on the temporal evolution of energetic electrons in a flaring coronal loop, Astron. Astrophys., 1992, vol. 258, pp. 542–548.
Melnikov, V.F., Gorbikov, S.P., and Pyatakov, N.P., Formation of anisotropic distributions of mildly relativistic electrons in flaring loops, Universal Heliophysical Processes, Proceedings of IAU Symposium 2008, no. 257, Gopalswamy, N. and Webb, D. F., Eds., 2009, pp. 323–328.
Zharkova, V.V., Kuznetsov, A.A., and Siversky, T.V., Diagnostics of energetic electrons with anisotropic distributions in solar flares-I. Hard X-rays bremsstrahlung emission, Astron. Astrophys., 2010, vol. 512, A8.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Charikov, Y.E., Shabalin, A.N. Influence of magnetic turbulence on the propagation of accelerated electrons and hard X-ray brightness distribution in solar flares. Geomagn. Aeron. 55, 1104–1111 (2015). https://doi.org/10.1134/S001679321508006X
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S001679321508006X