A survey of the Galactic center region in HCO+, H13CO+, and SiO

Abstract : Aims. A large-scale survey of the Galactic center region in the 3 mm rotational transitions of SiO, HCO+ and H13CO+ (beamsize ~3'6) was conducted to provide an estimate of cloud conditions, heating mechanisms, chemistry, and other properties. Results. Velocity channel maps, longitude-velocity maps, and latitude-velocity maps are presented. We identify 51 molecular clouds 33 of them belong to the Galactic center and 18 to disk gas. We can distinguish clearly between regions where the SiO or HCO+ dominate.