Abstract

The radio observations of temporal variations of the thermal cyclotron emission of sunspot-associated sources gain exclusively sensitive method for analysis of MHD oscillations in the magnetic tubes of sunspots. This was illustrated using observations of four active regions with the Nobeyama radio heliograph at wavelength λ = 1.76cm (Gelfreikh et al., Solar Physics, in press). In this paper we present future devepopment of the method analysing not only cycloton emission generated above sinspots but also thermal bremsstrhalung of active regions, usage parallel optical analysis of the oscillations and spectral microwave observations with radio telescope RATAN-600 also involved in this study. Besides earlier detected 3-min and 5-min periodic components some other periods were found in this study. Possible physiscal nature and role of adequate MHD waves is discussed. The radio observations open a new way to study propagations and resonance of MHD waves at the level of upper chromophere and lower corona unaccessable to optical methods.