High-resolution telescope and spectrograph observations of the quiet solar chromosphere and transition zone

A systematic program to observe the two-dimensional structure of the solar atmosphere and its temporal variation was conducted in connection with the third rocket flight of the High Resolution Telescope and Spectrograph (HRTS). A description is presented of the manner in which line intensities, Doppler shifts (velocities), and line widths are obtained from HRTS spectra. These quantities are derived for a single stigmatic slit spectra of the quiet sun. It is pointed out that an accurate wavelength scale can be derived from narrow Si I lines in the spectra. The intensity of chromospheric lines such as C I lambda 1560 is found to be largely the result of the structures forming the chromospheric network. A number of conclusions are drawn about quiet transition zone Doppler shifts (flows).