Abstract:
The heart of the Large Magellanic Cloud, 30 Doradus, is a complex region with a clear core-halo structure.
Feedback from the stellar cluster R136 has been shown to be the main source of energy creating multiple parsecscale expanding-shells in the outer region, and carving a nebula core in the proximity of the ionization source. We
present the morphology and strength of the magnetic fields (B-fields) of 30 Doradus inferred from the far-infrared
polarimetric observations by SOFIA/HAWC+ at 89, 154, and 214 μm. The B-field morphology is complex,
showing bending structures around R136. In addition, we use high spectral and angular resolution [C II]
observations from SOFIA/GREAT and CO(2-1) from APEX. The kinematic structure of the region correlates with
the B-field morphology and shows evidence of multiple expanding-shells. Our B-field strength maps, estimated
using the Davis–Chandrasekhar–Fermi method and structure-function, show variations across the cloud within a
maximum of 600, 450, and 350 μG at 89, 154, and 214 μm, respectively. We estimated that the majority of the 30
Doradus clouds are subcritical and sub-Alfvénic. The probability distribution function of the gas density shows that
the turbulence is mainly compressively driven, while the plasma beta parameter indicates supersonic turbulence.
We show that the B-field is sufficient to hold the cloud structure integrity under feedback from R136. We suggest
that supersonic compressive turbulence enables the local gravitational collapse and triggers a new generation of
stars to form. The velocity gradient technique using [C II] and CO(2-1) is likely to confirm these suggestions.
