Precise Millimeter‐Wave Laboratory Frequencies for CS and C 34 S

Abstract

Nine successive rotational lines in the ground vibrational state of CS and C 34 S between 96 GHz (J ¼ 2 1) and 500 GHz (10–9) were measured in the laboratory to an accuracy of a few kHz. When our measurements are combined with the submillimeter-wave measurements of Ahrens & Winnewisser, the entire rotational spectrum of both isotopic species is predicted to an accuracy of about 1 part in 10 8 up to 500 GHz and 5 parts in 10 8 near 1000 GHz. These frequencies should be useful for quantitative studies of cloud core collapse and star formation in the millimeter-and submillimeter-wave bands.