Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-30T06:26:59.319Z Has data issue: false hasContentIssue false

Electron-Beam Evolution in Partially Ionized Hydrogenic Plasma with Return Currents

Published online by Cambridge University Press:  12 April 2016

D. V. Syniavskii
Affiliation:
Physics Department, Kiev University, Kiev 252022, Ukraine
V. V. Zharkova
Affiliation:
Physics Department, Kiev University, Kiev 252022, Ukraine Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, Scotland, UK

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

This paper presents the kinetic equation solution for beam electrons injected during solar flares from the corona to the chromosphere, consisting of hydrogenic plasma with partial ionization. The electrons are considered to lose their energy both in collisional processes with the charged and neutral species of ambient plasma and in ohmic heating by return currents induced in the plasma by beam electrons. The evolution of the energy and angular distributions of energetic electrons is calculated as functions of the column density. The bulk of the electron-beam energy stored in low-energy electrons is shown to be lost in the ambient plasma heating, less via Coulomb collisions at the lower corona and more via ohmic dissipation at the upper chromosphere. More energetic electrons with energies above 120 keV can reach the chromospheric levels with a weak ionized plasma, where a decrease of the Coulomb collisions and the induced electric field of a return current produce beams as well directed as on the top boundary. The X-ray bremsstrahlung polarization is shown to be positive in the range 5%-10%. It is very sensitive to the emergent photon energies below 40 keV and to angles of view for all of the X-ray radiation range.

Subject headings: acceleration of particles — plasmas — Sun: flares — Sun: X-rays, gamma rays

Type
Poster Papers
Copyright
Copyright © The American Astronomical Society 1994

References

Aboudarham, J., & Henoux, J.C. 1986, A&A, 156, 73 Google Scholar
Diakonov, S.V., & Somov, B.V. 1988, Sol. Phys., 116, 119 CrossRefGoogle Scholar
Emslie, A.G. 1978, ApJ, 224, 241 Google Scholar
Emslie, A.G. 1980, ApJ, 235, 1055 CrossRefGoogle Scholar
Haug, E., Elwret, C., & Rausaria, R.R. 1985, A&A, 148, 115 Google Scholar
Landau, L.D. 1937, Zh. Eksper. Teoret. Fiz., 7, 203 Google Scholar
LaRosa, T.N., & Emslie, A.G. 1988, ApJ, 326, 997 Google Scholar
Leach, J., Emslie, A.G., & Petrosian, V. 1985, Sol. Phys., 96, 331 Google Scholar
Leach, J., & Petrosian, V. 1981, ApJ, 251, 781 CrossRefGoogle Scholar
Leach, J., & Petrosian, V. 1983, ApJ, 269, 715 Google Scholar
Li, P. 1991, Ph.D. thesis, Univ. Alabama, Huntsville Google Scholar
McClements, K.G. 1991, Vistas Astron., 34, 325 Google Scholar
McClements, K.G. 1992, A&A, 258, 542 Google Scholar
Nocera, L., Skrynnikov, Ju.I., & Somov, B.V. 1985, Sol. Phys., 97, 81 Google Scholar
Samarskii, A.A. 1989, Differential Scheme Theory (Moscow: Nauka), 616 Google Scholar
Shmeleva, O.P., & Syrovatskii, S.I. 1972, Soviet Astron.—AJ, 49 (No. 2), 145 Google Scholar
Somov, B.V., Syrovatskii, S.I., & Spektor, A.R. 1981, Sol. Phys., 73, 145 Google Scholar
Somov, B.V., & Tindo, I.P. 1978, Cosmic Res., 16, 555 Google Scholar
Tramiel, L.J., Chanan, G.A., & Novick, R. 1984, ApJ, 280, 440 Google Scholar
Zharkova, V.V., & Kobylinsky, V.A. 1989, Soviet Astron. Lett., 15, 366 Google Scholar
Zharkova, V.V., & Kobylinsky, V.A. 1992, Kinem. Phys. Terrest. Bodies, 32, 45 Google Scholar
Zharkova, V.V., & Kobylinsky, V.A. 1993, Sol. Phys., 143, 259 Google Scholar