Investigation of the polar coronal hole in the Sun with RATAN-600 in the centimeter radio range

Abstract

The article presents a brief overview of the main results of observations of the radio emission of a polar coronal hole (CH) on the Sun, obtained in a wide centimeter wavelength range (1.03-30.7) cm with the RATAN-600 radio telescope. The detected sharp decrease in the intensity of radio emission of the polar coronal hole at centimeter wavelengths (λ ≥ 6 cm) near the optical disk of the Sun and its absence at short wavelengths of observation (λ = 1.03, 1.38, 2.7 cm) are analyzed. The identity of the temperature properties of the polar CH and large lowlatitude CHs is discussed. During the discussion, a brief overview of some of the results of the study of the polar coronal hole in the Sun is given according to earlier observations, obtained with the radio telescopes LPRT, RATAN-600, RT-22 (CrAO), NoRH and others, as well as according to (EUV (SOHO) data and data from theoretical works.