A Sgr B2 kinetic temperature of about 47 K is derived based on observations of K components of the 9K-8K transition of CH3CCH. Interstellar line emission is detected in the 2 mm wavelength region from SO, (S-34)O, SO2, CH3OH, CH3CCH, CH3CH2CN, HC3N, and nine unidentified transitions. The methylacetylene K component data combined with the derived data reduction technique, demonstrates the utility of the molecule as a temperature probe of molecular clouds when two or more rotational transitions are observed. Evidence for the existence of interstellar HNO is presented, and an attempt is made to detect sulfuric acid, formic anhydride, and the 0-18 isotopic for CO2 in interstellar clouds and in the Venusian atmosphere during inferior conjunction.
Astrophysical Journal; vol. 251