Magnetic Field of Molecular Gas Measured with the Velocity Gradient Technique I. Orion A

Abstract Magnetic fields play an important role in the evolution of molecular clouds and star formation. Using velocity gradient technique (VGT) model, we measured magnetic field Orion A using 12 CO, 13 C 18 O(1-0) emission lines at a scale ∼0.07 pc. The B shows east–west orientation that is perpendicular to integral shaped filament large scale. VGT obtained from CO O are agreement with Planck 353 GHz dust polarization ∼0.55 Removal density effects by decomposition algorithm can significantly improve accuracy tracing CO(1-0) line. strengths seven subclouds, OMC-1, OMC-2, OMC-3, OMC-4, OMC-5, L 1641-N, NGC 1999, have also been estimated Davis–Chandrasekhar–Fermi Two Mach Numbers technique, these found be previous results far-infrared submillimeter wavelengths. At smaller scales, prove good method measure fields.