Quantum Analysis of the Blue-Green Bands of Titanium Oxide

Occurrence of the titanium oxide bands.—These bands form the most prominent characteristic of the $M$ type stars, reaching their maximum intensity at the $M8\mathrm{}$ type. They have been found by Fowler and others to be due to titanium oxide, and are usually referred to in the literature as Ti${\mathrm{O}}_2$ bands. The spectrum of the titanium bands is made up of at least two systems, one in the blue-green region, with which this paper deals, and one in the yellow-red. As yet no quantum relations have been found between the heads in the latter region. The bands of both systems degrade to the red.