A NEW SPECTRUM OF THE PO MOLECULE IN THE REGION $5300{\AA}-3800{\AA}$

Abstract

Several new bands in the region $5300{\AA}-3800{\AA}$ have been photographed at high resolution. The rotational analysis of these bands proves definitely that they belong to the PO molecule and involve the well known $B^{2}\Sigma$ state in their lower state. The upper levels of most of these bands are variously perturbed. All the bands so far analysed are of $^{2}\Sigma-^{2}\Sigma$ type. Half of about twelve new levels have much smaller B values and the other half about the same order as the ground state. Thus it appears that it may be possible to order these new levels into the various vibrational levels of two or more electronic states of Rydberg and non-Rydberg type. It is therefore hoped to present the quantitative results of a deperturbation study of these levels.