Ultra-violet extensions of the arc spectra of the alkaline earths: the absorption spectrum of calcium vapour

Abstract

The absorption spectrum of Ca 1 in the Schumann ultra-violet has been photographed by means of a King furnace and a 3 m vacuum spectrograph. Of the 82 lines found, 81 are classified reasonably in six series of two-electron transitions, viz. 4 1S0-3dnp,nf1,3P10, 3D10, the remaining line being probably 4 1S0-4p5s 1P10, which mixes strongly with the former series.