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C.E. Groppi (National Radio Astronomy Observatory)
The sub-mm wave portion of the electromagnetic spectrum is on the frontier of both scientific and technical research in astrophysics. Being a relatively young field, scientific advancement is driven by advancements in detector technology. In this talk, I discuss two observational projects based around heterodyne spectroscopy, and the design and construction of two sub-mm wave array receivers.
We have used multiple telescopes to observe several mm, submm transitions and continuum emission towards the R CrA molecular cloud core. Originally thought to be associated with high mass star formation, we find that the driving source behind the mm-wave emission is most likely a Class 0 protostar not yet identified in IR surveys. The close proximity of R CrA allows us to achieve high spatial resolution even with single dish mm-wave and sub-mm wave telescopes. With this resolution, we are able to disentangle the effects of infall, rotation and outflow. We also use vibrationally excited HCN emission to probe the protostellar accretion disk in a sample of nearby high and low mass protostars of varying ages. While these observations are difficult with single dish telescopes, we show the promise of the technique, and report results on 4 sources.
PoleStar is a 4 pixel heterodyne array built for operation in the 350\micron\ atmospheric window. It is in operation at the AST/RO telescope at the South Pole. This receiver has increased imaging speed in this band at AST/RO by a factor of ~20 compared to previous receiver systems. DesertStar is a 7 pixel, hexagonally close packed heterodyne array receiver built to operate in the 870\micron\ atmospheric window at the Heinrich Hertz Telescope in Arizona. This system should increase mapping speed in this wavelength regime by a factor of ~16. Both these receiver systems enable scientific projects requiring large area imaging that were previously impossible.
The author(s) of this abstract have provided an email address for comments about the abstract: cgroppi@nrao.edu
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Bulletin of the American Astronomical Society, 36 #2
© YEAR. The American Astronomical Soceity.