METER WAVELENGTH OBSERVATIONS OF THE QUIET SUN AND THE SLOWLY VARYING COMPONENT DURING DECLINING PHASE OF THE SOLAR-CYCLE

Two dimensional maps of the Sun at 164 MHz, obtained with the Nancay Radioheliograph from April to August 1984 are presented. The quiet sun emission and the slowly varying component far from sunspots are studied. The association of local emissions with the chromospheric calcium plages is pointed out and interpreted. The altitude of the radio sources is estimated. The comparison of the location of the sources with K-corona observations confirms previous results obtained for the minimum of the cycle. The brightness temperature of the coronal plateau, which is the radio counterpart of the coronal plasma sheet, is given.