Investigating the Physical Conditions in Extended System Hosting Mid-infrared Bubble N14

Abstract

Abstract To observationally explore physical processes, we present a multiwavelength study of a wide-scale environment toward l = 13.°7–14.°9 containing a mid-infrared bubble N14. The analysis of 12CO, 13CO, and C18O gas at [31.6, 46] km s−1 reveals an extended physical system (extension ∼59 pc × 29 pc), which hosts at least five groups of the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) 870 μm dust clumps at d ∼3.1 kpc. These spatially distinct groups/subregions contain unstable molecular clumps and are associated with several Class I young stellar objects (mean age ∼0.44 Myr). At least three groups of ATLASGAL clumps associated with the expanding H ii regions (including the bubble N14) and embedded infrared dark clouds, devoid of the ionized gas, are found in the system. The observed spectral indices derived using the Giant Metrewave Radio Telescope (GMRT) and THOR radio continuum data suggest the presence of nonthermal emission with the H ii regions. The high-resolution GMRT radio continuum map at 1280 MHz traces several ionized clumps powered by massive B-type stars toward N14, which are considerably young (age ∼103–104 yr). Locally, the early stage of star formation is evident toward all the groups of clumps. The position–velocity maps of 12CO, 13CO, and C18O exhibit an oscillatory-like velocity pattern toward the selected longitude range. Considering the presence of different groups/subregions in the system, the oscillatory pattern in velocity is indicative of the fragmentation process. All these observed findings favor the applicability of the global collapse scenario in the extended physical system, which also seems to explain the observed hierarchy.