CAII lines in a quiet region on the Sun I. Dynamic processes in the solar atmosphere

Abstract

We have studied oscillation processes in the quiet Sun outside a coronal hole at different levels of the solar chromosphere. The study was based on spectroscopic observations of ionized calcium lines (K, H, and 849.8 nm) obtained by the Sayan Solar Observatory’s Automated Solar Telescope (AST). Spectral analysis of time series for some parameters of the lines has been carried out. We have compared the results of this work with the results of our study of oscillation processes in quiet regions located at the base of a coronal hole. The oscillation power was found to be higher in the region of the quiet Sun outside a coronal hole. At the same time, for the regions under study there is a common tendency for the oscillation power to decrease with height for all frequency ranges, except for the low-frequency one, in most chromospheric structures. In structures with a weak magnetic field, the power increases with height to the lower chromosphere and decreases somewhat to the upper chromosphere.