Solar flare telescope and 10-cm new coronagraph

Abstract

Two new telescopes were built at the National Astronomical Observatory of Japan, i.e. the Solar Flare Telescope and the 10-cm New Coronagraph. The Solar Flare Telescope was constructed at Mitaka to make observations of photospheric velocity fields, vector magnetic fields, and Hα and continuum images of active regions simultaneously. The whole system will be completed in 1991. The 10-cm new coronagraph, which was developed to make precise measurements of the coronal intensity in several wavelengths, has already been in operation for one year at the Norikura Solar Observatory. At present the accuracy of about 10^-6 of the solar disk intensity is achieved in continuum light, but further improvement in the photometric accuracy remains to be done.