The motivation for this project is to understand the Galactic distribution of dense molecular gas associated with high-mass star formation regions and to characterize the protostellar and proto-cluster evolution of dense molecular clumps.
This work is a spectroscopic follow up of about 8000 sources discovered with the Bolocam Galactic Plane Survey (BGPS). The determination of fundamental parameters (such as sizes, masses, and luminosities), of these regions requires the knowledge of accurate distances. Here kinematic distances are measured with a spectroscopic survey comprised of simultaneous observations of the gas molecules HCO+ and N2H+ with the Heinrich Hertz Telescope toward the entire BGPS catalog sample. The kinematic distances are derived using a newly developed probability density function methodology which enables the characterization of the clump mass function and the mapping of the clumps onto the plane of the Galaxy. The evolutionary states of BGPS clumps will be probed by combining information from extant mid-infrared, far-infrared, millimeter, and radio continuum surveys with new observations of dense molecular gas. These data are needed to better understand the formation, evolution, and Galactic distribution of high-mass star forming regions in the Milky Way.
The derived velocities, kinematic distances, and a database of dense molecular clump properties and evolutionary information will be released to the scientific community and enhancing the BGPS archive. The database will be useful for planning efficient follow-up programs with Atacama Large Millimeter Array (ALMA) and the Expanded Very Large Array (eVLA) in the coming decade. This project has a strong participation of graduate and undergraduate students and will help to train the next generation of astronomers.
