Two new forbidden transitions of the O2 molecule have been found. They give rise to very faint absorption bands overlapping the much stronger forbidden [Formula: see text] bands previously described. The upper states are identified as [Formula: see text] and 3Δu respectively, both of which arise from the same electron configuration as the known states [Formula: see text] and [Formula: see text]. For the [Formula: see text] state the following vibrational and rotational constants have been determined: Te = 36678.91, ωe = 650.49, ωexe = 17.036, ωeye = −0.1056, ωeze = −0.00744, Be = 0.8261, αe = 0.0205, γe = −0.000830 cm.−1, γe = 1.597 × 10−5 cm. The constants are based on the assumption of a certain vibrational numbering which may have to be revised (increased). For the 3Δu state the data are quite fragmentary and only two rotational constants, B5 = 0.8177, B6 = 0.7915, and one vibrational quantum, [Formula: see text], have been determined. The bands of the [Formula: see text] system are very close to those of the [Formula: see text] system and represent in all probability the analogue in free O2 of the diffuse triplet bands of Wulf, Finkelnburg, and Steiner ascribed to O4. The positions of the new [Formula: see text] and 3Δu states agree closely with those predicted by Moffitt. Almost half of the unidentified features of the spectrum of the nightglow agree within 5 Å with the predicted positions of emission bands of the [Formula: see text] system.
Self-consistent calculation of the reactor antineutrino spectra including forbidden transitions
