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Hard X-ray generation in the turbulent plasma of solar flares

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Abstract

The influence of scattering of accelerated electrons in the turbulent plasma on the transformation of their distribution function is studied. The turbulence is connected with the emergence of magnetic inhomogeneities and ion-sound mode. The level of ion-sound turbulence is specified by the ratio W s/nk B T e = 10−3, while the value of magnetic fluctuations is δB/B = 10–3. Different initial angular distributions of the function of accelerated-electron source are regarded: from isotropic to narrow directional distributions. For the chosen energy-density values of the ion-sound turbulence and the level of magnetic fluctuations, it is shown that both types of turbulence lead to a qualitative change in the hard X-ray brightness along the loop, moreover their influence was found to be different. Models with magnetic fluctuations and the ion sound can be distinguished not only by the difference in the hard X-ray distribution along the loop but also by the photon spectrum.

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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.

    Article  Google Scholar 

  • Bai, T. and Ramaty, R., Backscatter, anisotropy, and polarization of solar hard X-rays, Astrophys. J., 1978, vol. 219, pp. 705–726.

    Article  Google Scholar 

  • Brown, J.C., Spicer, D.S., and Melrose, D.B., Production of a collisionless conduction front by rapid coronal heating and its role in solar hard X-ray bursts, Astrophys. J., 1979, vol. 228, pp. 592–597.

    Article  Google Scholar 

  • 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, no. 8, pp. 1021–1031.

    Article  Google Scholar 

  • Charikov, Yu.E. and Shabalin, A.N., Influence of magnetic turbulence on the propagation of accelerated electrons and hard X-ray brightness distribution in solar flares, Geomagn. Aeron. (Engl. Transl.), 2015, vol. 55, no. 8, pp. 1104–1111.

    Article  Google Scholar 

  • 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.

    Article  Google Scholar 

  • 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.

    Article  Google Scholar 

  • 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, id 176.

    Google Scholar 

  • Kudryavtsev, I.V. and Charikov, Yu.E., Kinetics of fast electrons in ion-acoustic waves in the turbulent plasma of solar flares, Astron. Zh., 1991, vol. 68, nos. 4–6, pp. 825–836.

    Google Scholar 

  • 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. 5063–5080.

    Article  Google Scholar 

  • 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.

    Google Scholar 

  • Melnikov, V.F., Gorbikov, S.P., and Pyatakov, N.P., Formation of anisotropic distributions of mildly relativistic electrons in flaring loops, Symp.–Int. Astron. Union, 2009, vol. 257, pp. 323–328.

    Google Scholar 

  • Tsytovich, V.N., Teoriya turbulentnoi plazmy (Theory of Turbulent Plasma), Moscow: Atomizdat, 1971.

    Google Scholar 

  • 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, id A8.

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Authors and Affiliations

  1. Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg, 194021, Russia

    Yu. E. Charikov & A. N. Shabalin

  2. Peter the Great St. Petersburg Polytechnic University, St. Petersburg, 195251, Russia

    Yu. E. Charikov

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  1. Yu. E. Charikov
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  2. A. N. Shabalin
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Correspondence to Yu. E. Charikov.

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Charikov, Y.E., Shabalin, A.N. Hard X-ray generation in the turbulent plasma of solar flares. Geomagn. Aeron. 56, 1068–1074 (2016). https://doi.org/10.1134/S0016793216080041

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  • DOI: https://doi.org/10.1134/S0016793216080041

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