HCN, CO, CS, CN, AND CO-B2)( OBSERVATIONS OF COMET HYAKUTAKE (1996)

In March and April 1996 we observed the comet Hyakutake (1996 B2) with the KOSMA 3-m telescope. We detected the J = 2-1 and 3-2 transitions of CO, and the J = 3-2 and 4-3 transitions of HCN on several days duri ng this period. In addition we detected CS J = 7-6 on one occasion. We observed, but did not detect, several transitions of CN (N = 2-1 and N = 3-2), and CO+ N = 3-2. From our results we derive production rates of the different molecules or upper limits. The simultaneous observat ions of different transitions and different molecules allow a comparis on of those rates and of the assumed excitation model. The KCN spectra show variability by about 50% on a time scale of hours. (C)1998 Publi shed by Elsevier Science Ltd. All rights reserved.