A&A 463, 1165-1170 (2007)
DOI: 10.1051/0004-6361:20065956
High-frequency waves in solar and stellar coronae
V. G. Ledenev1, V. V. Tirsky2, and V. M. Tomozov11 Institute of Solar-Terrestrial Physics, Russian Academy of Sciences, PO Box 4026, Irkutsk, Russia
e-mail: leden@iszf.irk.ru
2 Institute of Laser Physics, Russian Academy of Sciences, Irkutsk Branch, Russia
(Received 3 July 2006 / Accepted 15 November 2006)
Abstract
On the basis of a numerical solution of dispersion equation we analyze characteristics of
low-damping high-frequency waves in hot magnetized solar and stellar coronal plasmas in conditions when the
electron gyrofrequency is equal or higher than the electron plasma frequency. It is shown that branches that
correspond to Z-mode and ordinary waves approach each other when the magnetic field increases and become
practically indistinguishable in a broad region of frequencies at all angles between the wave vector and the
magnetic field. At angles between the wave vector and the magnetic field close to
, a wave branch with an
anomalous dispersion may occur. On the basis of the obtained results we suggest a new interpretation of such
events in solar and stellar radio emission as broadband pulsations and spikes.
Key words: plasmas -- turbulence -- radiation mechanisms: non-thermal -- Sun: flares -- Sun: radio radiation -- stars: flare
© ESO 2007

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