Srg C Region CII datacubes

These observations are analyzed in conjunction with ancillary maps of the CO(2-1) transition and its isotopologues from the APEX telescope. [CII] emission is widespread, showing a continuous structure extending from Sgr A to Sgr C with complex morphology. The bulk emission arises at negative radial velocities, consistent with Galactic rotation.

The most prominent feature is the giant Sgr C HII region, where [CII] reveals an expanding, ring-like shell interpreted as a photo-dissociation region (PDR). Kinematic modelling yields an expansion velocity of 23km/s and a dynamical age of about 0.13Myr. Our analysis suggests that stellar winds from known massive stars are insufficient to power the observed expansion, pointing toward alternative drivers like a buried supernova.

Finally, we find a striking spatial association between this shell and a non-thermal radio filament, indicating that the shell's expansion has triggered high-mass star formation at its edge.