Collision of molecular outflows in the L1448-C system

Artikel i vetenskaplig tidskrift, 2023

We present a study of the central zone of the star-forming region L1448 at 217-230 GHz (∼1.3 mm) using Atacama Large Millimeter Array observations. Our study focuses on the detection of proto-stellar molecular outflows and the interaction with the surrounding medium towards sources L1448-C(N) and L1448-C(S). Both sources exhibit continuum emission, with L1448-C(N) being the brightest one. Based on its spectral index and the associated bipolar outflow, the continuum emission is the most likely to be associated with a circumstellar disk. The 12CO(J = 2→1) and SiO(J = 5→4) emissions associated with L1448-C(N) trace a bipolar outflow and a jet oriented along the northwest-southeast direction. The 12CO(J = 2→1) outflow for L1448-C(N) has a wide-open angle and a V-shape morphology. The SiO jet is highly collimated and has an axial extent comparable with the 12CO(J = 2→1) emission. There is not SiO(J = 5→4) emission towards L1448-C(S), but there is 12CO(J = 2→1) emission. The observations revealed that the red-shifted lobes of the 12CO(J = 2→1) outflows of L1448-C(N) and L1448-C(S) are colliding. As a result of this interaction, the L1448-C(S) lobe seems to be truncated. The collision of the molecular outflows is also hinted by the SiO(J = 5→4) emission, where the velocity dispersion increases significantly in the interaction zone. We also investigated whether it could be possible that this collision triggers the formation of new stars in the L1448-C system.