Outflow and infall in a sample of massive star forming regions. II. Large-scale kinematics

We present maps of seven sources selected from our previous paper in SiO (J = 8-7) and HCO+ and (HCO+)-C-13 (J = 4-3), which were obtained using HARP-B on the James Clerk Maxwell Telescope. We find that four out of our seven sources have infall signatures based on their HCO+ emission profiles. From our maps, we have determined the extent of both the outflowing and infalling regions toward these sources, and constrained the amount of infalling and outflowing mass, as well as the mass infall rate for each massive star forming region. From our SiO observations, we estimate the source luminosity required to shock the surroundings of these massive star forming regions and find luminosities similar to those of the H II regions themselves. We find that the ratio between our infall and outflow masses is less than 1, suggesting high mass entrainment rates in the molecular outflows. We also find that the large-scale molecular infall rate toward G10.6-0.4 is comparable to the small-scale molecular infall rate found in previous studies.