Estimation of Solar Observations with the Five-hundred-meter Aperture Spherical Radio Telescope (FAST)

TL;DR

This paper estimates optimal observational strategies for the FAST radio telescope to safely observe the Sun, recommending specific angular separations to prevent receiver damage across different frequency bands.

Contribution

It provides practical guidelines for solar observations with FAST, including recommended angular separations to ensure safety and data quality.

Findings

Direct pointing at the Sun exceeds safe power levels.

A separation of about 2° is needed at 1.25 GHz.

A larger separation is required at lower frequencies.

Abstract

We present the estimation of the solar observation with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). For both the quite Sun and the Sun with radio bursts, when pointing directly to the Sun, the total power received by FAST would be out of the safe operational range of the signal chain, even resulting in the damage to the receiver. As a conclusion, the Sun should be kept at least $\sim 2^{\circ}$ away from the main beam during the observing at $\sim 1.25 {\ \rm GHz}$. The separation for lower frequency should be larger. For simplicity, the angular separation between the FAST beam and the Sun is suggested to be $\sim 5^{\circ}$ for observations on 200 MHz or higher bands.