It is shown that radio emission of microbursts in solar active regions
is the manifestation of noise storms at the fundamental plasma frequency,
and is the result of instabilities propagating at the tops of coronal
loops. Noise storms are perceived as large-scale active formations,
covering the layers of the solar atmosphere from the tens to hundred
thousand kilometers above the photosphere.
Collaboration with the Nancay Decimetric Radio Telescope (France).
A method for determining the height of the corona base above sunspots was proposed. The technique is based on the comparison of radio astronomical and magnetographic observations on the RATAN-600, the values of which are enclosed in the range of 500 and 4500km. The magnetic field, determined from the third harmonic of the gyrofrequency, reaches its maximum value at the base of the solar corona and is at odds with the value, determined from the second harmonic, which is inconsistent with theoretical expectations.