| Abstract : | Magnetic fields play a crucial role in the formation and evolution of molecular clouds. Hub-filament systems (HFSs) are the potential sites of protocluster and massive star formation and play a key role in mass accumulation to initiate the massive star formation. The role of magnetic fields in such regions is not well understood. We present preliminary results based on the sub-millimeter (850 µm) dust continuum polarization observations towards a massive star-forming Cep A using JCMT SCUBA-2/POL-2. We found that the polarization fraction (P) decreases with intensity (I) with the power-law index of α = 0.7. P, on the other hand, deviates from the general distribution and exhibits a relatively lower α of 0.4 for I > 220 mJy/beam. This implies that the dust grains in the densest portion of the core are better aligned where massive star formation activity is prominent. Despite the uniform large-scale magnetic field structure on the outskirts, the magnetic field morphology is found to be complex in the clump region of Cep A. We have analyzed the correlations between the structure of B-fields, gravity, and outflows. We found that the magnetic and gravitational fields are aligned along the N–S region; whereas outflow orientations are better correlated with B-fields along the E–W region. Based on the energy parameters, we will talk about how important the magnetic fields are in comparison to gravity, turbulence, and outflows. |
