Submillimeter observations of the 1991 July 11 total solar eclipse

摘要: We present observations of the 1991 July 11 total solar eclipse at 850 μm made with Caltech Submillimeter Observatory (CSO) on Mauna Kea. find that limb is 3380±140 km above visible limb. also there a 10% brightening in outer 7″ disk, and we measure central brightness temperature 6400±700 K. These results require upper chromosphere not be hydrostatic equilibrium, higher electron density than predicted by standard (VAL) model