Abstract

For the study of high energy phenomena on the sun during the maximum period of the 22nd solar activity cycle, we started to construct a radio heliograph at Nobeyama Radio Observatory. The operating frequency was selected to be 17 GHz to catch the emission from the accelerated electrons in solar flares. The 17 GHz Radio Heliograph consists of T-shaped array of 490 m in the E-W direction and 220 m in N-S direction with 84 antenna elements. The heliograph can map the whole sun with 10-arcsec spatial resolution and with 50-millisecond temporal resolution.