Abstract

Contributed Talk - Splinter StarFormation   (MW-1250)

Disentangling the origins of streamers towards IRAS 2A with STING

Lauren Mason (1), Jaime E. Pineda (1), and the PRODIGE team
1: Max-Planck-Institut für extraterrestrische Physik

Streamers are asymmetric accretion flows channelling material from large-scale environments onto young protostellar systems. Although frequently observed towards these systems, their origins are not well understood. The close binary protostellar system IRAS 2A shows a quadrupolar velocity pattern with evidence for two possible streamers (Jørgensen et al. 2022). We present an analysis of the molecular environment towards IRAS 2A using ~1'' (~300 au) resolution NOEMA observations from the PRODIGE large program. We identify two asymmetric inflow candidates. The first (S1) is confirmed as a streamer using STING, our new open-source Python package which fits the free-falling, rotating streamline model of Mendoza et al. (2009) to streamer candidate data. The second (S2) remains a streamer candidate. The two flows are chemically distinct: S1 is detected in D2CO but not DCN, while S2 shows the opposite, implying different origins or chemical histories. Using DCO+ observations from the IRAM 30m ANTIHEROES program, we morphologically trace both flows to larger scales, where two curved structures extend southwards from IRAS 2A. The structure associated with S1 connects to a known filament in NGC 1333 (Chen et al. 2020), suggesting material is channelled from the filament onto the system via the streamer. There is currently no known filament in the direction of S2. Together, these results provide the first evidence of a protostellar system simultaneously accreting chemically distinct material along two independent pathways with different origins.