Distribution of centimeter-wave brightness temperature of solar polar region

Brightness temperatures and electron density in the solar polar coronal region on the basis of MW observations

“…This effect is absent at short centimeter waves, e.g., 1.03-2.7 cm. The brightness temperature (T b ) distri butions with a distance in the solar polar region obtained at short wavelengths (λ = 1.38, 1.03, and 2.0 cm) on March 29, 2006 are close to each other (Golubchina and Korzhavin, 2013a).…”

“…Sometimes, electron concentrations for the middle corona are calculated by the revised Baumbach formula (Zheleznyakov, 1964;Golubchina and Korzhavin, 2013a). In this work, the electron concentration was found from the brightness temperature distributions calculated from RATAN 600 observations of the solar eclipse of March 29, 2006.…”

“…The brightness temperatures for Moon rings were specified according to literature data (Zheleznyakov, 1964) and through a choice of short waves of 1.03 (Fig. 3) and 1.38 cm (Golubchina and Korzhavin, 2013a).…”

“…Approximation of the real observa tion record to the model curve witnesses the choice of the correct distribution of brightness temperatures with the distance from the limb to two solar radii. The results of such investigations are given in detail in Gol ubchina, et al, 2011;Golubchina and Korzhavin, 2013a). The analysis of the brightness temperature dis tributions found with the distance at different wave lengths (1.03-30.7 cm) has shown a sharp decrease in the solar brightness temperature T b from 45000 K at the distance r/Rs = 1.005 to 10000 K at r/Rs = 1.03 at a decimeter wave of 13 cm (here r/Rs is the distance from the solar center in fractions of the solar radius).…”

“…In this work, the electron concentration was found from the brightness temperature distributions calculated from RATAN 600 observations of the solar eclipse of March 29, 2006. The AP of the RATAN 600 radio telescope is a knife; its sizes for a series of waves are given in (Golubchina and Korzhavin, 2013a). We selected observations at the shortest waves, i.e., 1.03 and 1.38 cm, for the AP to go beyond the polar coronal hole over the North Pole of the Sun minimally.…”