2019ApJ...875..138D

To probe the ongoing physical mechanism, we studied a wide-scale environment around AFGL 5142 (area ∼25 pc x 20 pc) using a multiwavelength approach. The Herschel column density (N(H₂)) map reveals a massive inverted Y-like structure (mass ∼6280 M_☉), which hosts a pair of elongated filaments (lengths >10 pc). The Herschel temperature map depicts the filaments in a temperature range of ∼12.5-13.5 K. These elongated filaments overlap each other at several places, where N(H₂) > 4.5 x 10²¹ cm^–2. The ¹²CO and ¹³CO line data also show two elongated cloud components (around -1.5 and -4.5 km s^–1) toward the inverted Y-like structure, which are connected in the velocity space. First moment maps of CO confirm the presence of two intertwined filamentary clouds along the line of sight. These results explain the morphology of the inverted Y-like structure through a combination of two different filamentary clouds, which are also supported by the distribution of the cold H I gas. Based on the distribution of young stellar objects (YSOs), star formation (SF) activities are investigated toward the inverted Y-like structure. The northern end of the structure hosts AFGL 5142 and tracers of massive SF, where high surface density of YSOs (i.e., 5-240 YSOs pc^–2) reveals strong SF activity. Furthermore, noticeable YSOs are found toward the overlapping zones of the clouds. All this observational evidence supports a scenario of collision/interaction of two elongated filamentary clouds/flows, which appears to explain SF history in the site AFGL 5142.