| This dissertation presents submillimeter polarimetry methods and scientific results. The scientific results focus on revealing the magnetic field structure of giant molecular clouds (GMCs). The basic principles, instrumentation, observing strategy, and data analysis methods of submillimeter polarimetry are introduced. The scientific data were acquired by SPARO during the observing campaign of Austral Winter 2003. SPARO is a 450 mum polarimeter used with a two-meter telescope at South Pole. We mapped four GMCs: NGC 6334, the Carina Nebula, G333.6-0.2, and G331.5-0.1. Comparing the mean field direction with optical polarimetry data, we suggest that field direction tends to be preserved during GMC formation. By comparing the observed field disorder with that from GMC simulations, we conclude that the magnetic field energy density is at least comparable to that of turbulence. |
