Design, construction and performance of a spectrograph for recording the flash spectrum during solar eclipse

Physical parameters of the solar chromosphere are determined by observing the flash spectrum of a total solar eclipse. Flash spectrum is a phenomenon that is only visible a few second before and after the totality of a solar eclipse. Specific spectrograph design is needed to suit the purpose of the flash spectrum recordings. A spectrograph has been designed and built to capture the flash spectrum during the total solar eclipse of 2009. The design and construction of the spectrograph is described in this paper. Some emission lines from the solar chromosphere were recorded. The observation was less successful due to some technical problems and weaknesses of the spectrograph. This led to the second design of the spectrograph. The improved version spectrograph covered the spectral range from 4750Å to 6750 Å with dispersion of 1.5 Å/pixel. Chromospheric spectrum was recorded during the annular solar eclipse of 2010.