Observations of the 3.4-mm HCO+ Line toward the Galactic Center

Abstract

3.4-mm line of HCO+ has been mapped toward the galactic center. The telescope used was the 6-m mm-wave telescope at the Tokyo Astronomical Observatory, equipped with a GaAs Schottky barrier diode mixer and a 256-ch filter bank of 1-MHz resolution. Fig. 1 shows the observed positions on the antenna temperature contour map of HCN(Fukui et al. 1977). Intensive observations were made of the line SR where the HCN emission is strongest. Fig. 2 shows the HCO+ profile as well as the HCN profile, both of which are averages along SR().