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Radio emission of the quiet Sun is considered to be due to thermalbremsstrahlung emission of the hot solar atmosphere. The properties of thequiet Sun in the microwave band have been well studied, and they can be welldescribed by the spectrum of bremsstrahlung emission. In the meter-wave anddecameter-wave bands, properties of the quiet Sun have rarely been studied dueto the instrumental limitations. In this work, we use the LOw Frequency ARray(LOFAR) telescope to perform high quality interferometric imaging spectroscopyobservations of quiet Sun coronal emission at frequencies below 90~MHz. Wepresent the brightness temperature spectrum, and size of the Sun in thefrequency range of 20-80~MHz. We report on dark coronal regions with lowbrightness temperature that persist with frequency. The brightness temperaturespectrum of the quiet Sun is discussed and compared with the bremsstrahlungemission of a coronal model and previous quiet Sun observations.

Imaging of the Quiet Sun in the Frequency Range of 20-80 MHz