We present the first detailed multi-tracer observation of a 5-pc long outer Galaxy filament, G183, and the massive young stellar object (YSO) IRAS, 5480+2545 associated with it. Using the IRAM 30-m telescope at łambda = 1. 4 and 3, mm, we probed the molecular gas distribution at angular resolutions of ∼ 12 -28 (0. 1--0. 3, pc at d = 2. 1, kpc). The velocity-resolved observations conclusively show a main filament with a skeleton of ridges. The main filament is a 5, pc long velocity-coherent structure with a continuous and quiescent velocity field along its length up to the star-forming hub that accretes mass from the filament. The internal gas kinematics of most of the G183 filament is dominated by thermal motions (σ_̊m NT/cₛ∼ 1) and large-scale velocity gradients arising due to outflows and accretion of matter in the massive YSO. The dispersion-size relation almost up to 1, pc is consistent with Larson's law, suggesting that the origin of the filament is a turbulence cascade. The massive YSO, S1, with no corresponding radio continuum detection is characterized as a high-mass protostellar object with a mass of 156, , ), respectively. In comparison to the inner Galaxy high-mass star-forming filaments forming massive stars, G183 has a lower column density; however, the accretion and outflow rates in S1 are similar. The detection of hydrocarbons such as ̧hthrcn and and an M/L ratio of 0. 04. We identify a kinematic signature of the accretion of material from the filament onto the YSO, S1. The rates of molecular gas accretion and entrainment in S1 are estimated to be 8. 6 and 2. 6 (in units of 10 -4 -1 indicates the presence of hot-core chemistry in S1. These results highlight the universality of physical processes involved in massive star formation across a range of Galactic environments.
Mookerjea et al. (Fri,) studied this question.