C¹⁸O and HNCO in the Galactic Centre

Extract

Using the SEST, we have observed 554 positions with a spacing of 45″ in the C¹⁸O(J = 1 → 0) and HNCO(J_kk′ = 5₀₅ → 4₀₄) lines. The data covers most of the Sgr A region including the Arc. Many of the dominant clouds in the GC region (see e.g. Güsten et al. 1981, A&A 103, 197; Bally et al. 1987, ApJS, 65, 13) are readily identified in the total integrated C¹⁸O and HNCO maps (Fig. 1). The results will be published in A&AS and will include intensity maps with 5 km s^–1 velocity resolutions, as well as galactic longitude-velocity and galactic latitude-velocity maps. J = 2 → 1 C¹⁸O observations are planned for selected regions. The objectives of the project are twofold: 1. Geometrical, morphological, and dynamical relationships between the molecular regions and the radio continuum sources. 2. Heating mechanisms in GC molecular clouds.