3-03
Lars Bonne
SOFIA Science Center/USRA
The impact of stellar feedback in the young Vela C molecular cloud
We present observations of the [CII] and [OI] fine-structure lines from the SOFIA FEEDBACK Legacy Survey towards the bipolar HII region RCW 36, centered on a 1 Myr old OB cluster, in the Vela C molecular cloud. The SOFIA observations show that the [CII] 158 micron and [OI] 63 micron lines are self-absorbed, and reveal expanding shells in the bipolar cavities. The expansion timescales suggest that the observed bipolar HII region, formed by expansion from a sheet, is a short phase in the evolution of RCW 36. The observations further show that the stellar feedback can locally break through the dense swept up gas, shapes the magnetic field which provides negligible resistance for the expansion and drives an increased turbulence level in the swept up gas which will affect the second generation of star formation. Complementary Chandra observations trace the hot plasma, due to stellar winds, in RCW 36 which can drive the observed expansion seen with [CII]. This hot plasma shows important leakage from RCW 36 that has lost more than 90% of the injected energy by stellar winds. This strongly suggests the presence of large 'holes' in the Vela C cloud structure before the onset of stellar feedback. Kinematically resolved [CII] observations thus, among other things, provide a unique view on how stellar feedback disrupts a molecular cloud and affects future star formation.
