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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 parsec-scale 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 μ m. 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 μ G at 89, 154, and 214 μ m, 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. [ABSTRACT FROM AUTHOR]

We report SOFIA/GREAT observations of high-J CO lines and [C ii ] observations of the super star cluster candidate H72.97-69.39 in the Large Magellanic Cloud (LMC), which is in its very early formation stage. We use our observations to determine if shocks are heating the gas or if photon-dominated regions (PDRs) are being heated by local far-UV radiation. We use a PDR model and a shock model to determine whether the CO and [C ii ] lines arise from PDRs or shocks. We can reproduce the observed high-J CO and [C ii ] emission with a clumpy PDR model with the following properties: a density of 104.7 cm−3, a mass of 104M⊙, and UV radiation of 103.5 in units of Draine field. Comparison with the ALMA beam-filling factor suggests a higher density within the uncertainty of the fit. We find the lower-limit [C ii ]/total infrared (TIR) ratio (ϵ) traced by [C ii ]/TIR to be 0.026%, lower than other known young star-forming regions in the LMC. Our shock models may explain the CO (16−15) and CO (11−10) emission lines with shock velocity of 8–11 km s−1, pre-shock density of 104–105 cm−3, and GUV = 0 in units of Draine field. However, the [C ii ] line emission cannot be explained by a shock model, thus it is originating in a different gas component. Observations of [O i ] 63 μm predicted to be 1.1 × 10−13 W m−2 by PDR models and 7.8 × 10−15 W m−2 by shock models will help distinguish between the PDR and shock scenarios. [ABSTRACT FROM AUTHOR]