We present new H-band polarization measurements of stars in and behind the southern region of the Orion A Cloud, L1641N, taken with the WIRC+Pol spectropolarimeter at the Palomar Observatory, in order to study the structure of the magnetic field in this nearby star-forming region. We concentrate our observations on stars that lie, in projection, on the outskirts of cores. As such, our observations probe the magnetic field orientation in the medium to low-density regions of the cloud. We use the 12CO(1-0) and 13CO(1-0) molecular line maps from the CARMA-NRO Orion survey to determine the gas structure and kinematics and to compare the field structure orientation with the morphology of the diffused gas in the south-central region of Orion A. In addition, we conducted a similar analysis of the gas structure and magnetic field behavior in OMC-1, one of the densest and most active regions in the cloud. using thermal dust emission-derived magnetic fields from the JCMT BISTRO Survey (sub-millimeter) and SOFIA HAWC+ (far-infrared). From comparing the relative plane of sky orientation of the magnetic field with gas structures, we find that in OMC-1 the magnetic field tends to be aligned with the outflows in the region, indicating that outflows may influence the magnetic field structure or vice versa. In addition, from combining gas and magnetic field orientation maps, we find that structures in the 12CO map are, on average, more aligned with the magnetic field compared to 13CO and C18O maps, hinting at decreased magnetic field influence towards denser regions in the cloud.
[Poster PDF File]