The predicted infrared spectrum of ZrO and its possible presence in S stars

Abstract

The unidentified absorption feature at 9730 ± 5 A observed in the spectra of pure S stars is provisionally identified with the predicted 9732 A (0, 0) band of the e `IT-c `z\ transition of ZrO molecule. Relative band strengths and band head positions of this transition in the 8300- 12 500 A region are presented to assist both laboratory and stellar spectral studies. The insistent need for the laboratory study of gas phase infrared spectrum of ZrO is accentuated