Solar Spectra

(a) Solar spectrum in the range from 66 to 150 nm; this is the full range of detector B (KBr cathode). The intensity is squarerooted to compress the dynamical range and displayed in arbitrary units. The reason for the gap around 121.5 nm is Lyman-alpha - the brightest line in the Solar EUV spectrum - which cannot be observed on the disk.
This spectrum was acquired at the north limb.

(b) Spectral band around 93 nm including the transition from the Lyman series to the Lyman continuum; Lyman lines are optically thick and show selfabsorption.

(c) Spectral band around 131 nm including many spectral lines; more than 200 spectral lines have been identified so far. (Even more now!) (Werner Curdt)

(a) (b) (c)