H 2 0 + Ions in Comets: Comet Kohoutek (1973f) and Comet Bradfield (1974b)

• Published in: International Astronomical Union Colloquium 1976, Vol.25 (Part1), p.199-205
• Main Authors: Wehinger, Peter, Wyckoff, Susan
• Format: Article
• Language: English
• ISSN: 0252-9211
• DOI: 10.1017/S0252921100500864

Herzberg and Douglas (1973) first predicted that the H 2 0 + ion might be observable in comet tail spectra. Subsequently Lew and Heiber (1973) discovered the laboratory spectrum of H 2 0 + . In October and November 1973, Herbig (1973), Benvenuti and Wurm (1974), and Wehinger and Wyckoff (1974) reported unidentified features in the tail spectrum of comet Kohoutek. On the basis of these observations, Herzberg and Lew (1974) made a tentative identification by pointing out coincidences with several strong low-lying lines in the H 2 0 + spectrum. Further observations were obtained in November 1973 and January 1974 at the Wise Observatory and by Herbig at the Lick Observatory. Six vibronic bands (5-0 through 10-0), including a total of approximately 50 rotational lines were identified with laboratory H 2 0 + spectrum (Wehinger et al. 1974). The predicted spin splitting of those lines with 2 to 4 Å separation was observed in the coude spectra of Herbig.