LMC N113 and N159W ALMA para-H_2_CO datacubes

We mapped the kinetic temperature structure of two massive star-forming regions, N113 and N159W, in the Large Magellanic Cloud (LMC). We have used ∼1.6" (∼0.4pc) resolution measurements of the para-H2CO JKaKc=303-202, 322-221, and 321-220 transitions near 218.5GHz to constrain RADEX non local thermodynamic equilibrium models of the physical conditions. The gas kinetic temperatures derived from the para-H2CO line ratios 322-221/303-202 and 321-220/303-202 range from 28 to 105K in N113 and 29 to 68K in N159W. Distributions of the dense gas traced by para-H2CO agree with those of the 1.3mm dust and Spitzer 8.0um emission, but they do not significantly correlate with the H emission. The high kinetic temperatures (Tkin≳50K) of the dense gas traced by para-H2CO appear to be correlated with the embedded infrared sources inside the clouds and/or young stellar objects in the N113 and N159W regions. The lower temperatures (Tkin<50K) were measured at the outskirts of the H2CO-bearing distributions of both N113 and N159W. It seems that the kinetic temperatures of the dense gas traced by para-H2CO are weakly affected by the external sources of the Hα emission. The non thermal velocity dispersions of para-H2CO are well correlated with the gas kinetic temperatures in the N113 region, implying that the higher kinetic temperature traced by para-H2CO is related to turbulence on a ∼0.4pc scale. The dense gas heating appears to be dominated by internal star formation activity, radiation, and/or turbulence. It seems that the mechanism heating the dense gas of the star-forming regions in the LMC is consistent with that in Galactic massive star-forming regions located in the Galactic plane