This project will fund the commissioning of a sub-mm polarimeter to be used at the Caltech Submillimeter Observatory. The optics of the polarimeter will split the incoming waves into two polarizations that will then be recorded simultaneously on two 144-pixel subsections of the existing 288-pixel imaging array at the observatory. The polarimeter will be used for various investigations, including detection of polarized emission from plasma near the event horizon of the black hole at the Galactic center; observations of turbulent eddies in magnetized clouds, for the purpose of testing theoretical ideas concerning how turbulence controls star formation; and determination of the shape of magnetic fields in the immediate vicinity of protostars where initial collapse has occurred.
