Radio interferometric observations of the Sun using commercial dish TV antennas

Abstract

The radio astronomy group in the Indian Institute of Astrophysics (IIA) has been carrying out routine observations of radio emission from the solar corona at low frequencies (≈40 – 440 MHz) at the Gauribidanur observatory, about 100 km north of Bangalore. Since IIA has been performing regular observations of the solar photosphere and chromosphere using different optical telescopes in its Kodaikanal Solar Observatory (KSO) also (see https://www.iiap.res.in/kodai.htm), the possibilities of obtaining two-dimensional radio images of the solar chromosphere using low-cost instrumentation to supplement the optical observations are being explored. As a part of the exercise, recently the group had developed prototype instrumentation for interferometric observations of radio emission from the solar chromosphere at high frequencies (≈11.2 GHz) using two commercial dish TV antennas. The hardware set-up and initial observations are presented.