RADIO PHYSICS AND RADIO ASTRONOMY

PACS number: 96.60.-j

Purpose: The radio emission propagation of solar radio bursts in the solar corona which sources are located on the far side of the Sun relative to the observer on Earth is studied.

Design/methodology/approach: Using the piecewise linear approximation of the beam path in various models of electron density in corona, we find out the impact of these models on the propagation effects of radio emission from the far side of the Sun in approximation of geometric optics.

Findings: It is shown that if as a model of the solar corona one chooses the plasma density decreasing in solar corona with distance from photosphere, the radiation of limb-behind burst sources cannot be recorded by ground-based radio astronomy instruments due to radio emission reflection in the direction outward the Earth.

Conclusions: The arguments to explain the possibility of groundbased observations of limb-behind bursts due to the influence of coronal mass ejections on the solar corona density from active spots near the solar limb are proposed.

Key words: Sun, upper corona, decameter radio emission, electron density distribution, inhomogeneous layered medium

Manuscript submitted 24.12.2015

Radio phys. radio astron. 2016, 21(1): 3-13

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