Merging Filaments and Hub Formation in the G083.097$+$03.270 Molecular Complex

TL;DR

This study reveals a hub-filament system in the G083.097+03.270 region where filament merging and velocity gradients drive mass accumulation, leading to massive star formation, supporting the 'filaments to clusters' paradigm.

Contribution

It provides detailed observational evidence of filament merging and associated kinematics as mechanisms for massive star formation in a specific molecular complex.

Findings

Two distinct filaments with separate velocities are merging at a dense hub.

Velocity gradients and turbulence increase toward the hub, indicating mass inflow.

Presence of Class I sources and a massive outflow confirms active star formation.

Abstract

We uncover a hub-filament system associated with massive star formation in the G083.097$+$03.270. Diagnosed with simultaneous $^{12}$CO, $^{13}$CO, and C$^{18}$O line observations, the region is found to host two distinct and elongated filaments having separate velocity components, interacting spatially and kinematically, that appear to have seeded the formation of a dense hub at the intersection. A large velocity spread at the hub in addition to clear bridging feature connecting the filaments in velocity are indicating merging of filaments. Along the filaments axis, the velocity gradient reveals a global gas motion with an increasing velocity dispersion inward to the hub signifying turbulence. Altogether, the clustering of Class I sources, a high excitation temperature, a high column density, and presence of a massive outflow at the central hub suggest enhanced star formation. We propose that merging of large-scale filaments and velocity gradients along filaments are the driving factors in the mass accumulation process at the hub that have sequentially led to the massive star formation. With two giant filaments merging to coincide with a hub therein with ongoing star formation, this site serves as a benchmark for the `filaments to clusters' star-forming paradigm.