Published online by Cambridge University Press: 25 May 2016
Sgr B2, located at a distance of ∼100 pc from the Galactic center, is one of the most active, recent massive-star formation regions in the Galaxy. Based on the 13CO (J = 1–0) line data taken with the Nobeyama 45 m telescope, we presented a cloud collision scenario as the triggering mechanism of the burst of massive-star formation there (Hasegawa et al. 1994). In order to obtain further evidence supporting our model, we observed the Sgr B2 molecular cloud in various molecular lines with the 45 m telescope in 1992 February. Twelve points each with 20″ spacings were observed along several strips 3.67′ long at constant galactic longitudes through the major HII region complexes. Here we report the results of the two lines in the 110 GHz band, C18O (J = 1–0) and HNCO (50,5–40,4). Full description of the observations will be given elsewhere (Sato et al. 1997).