JWST-ALMA study of a hub-filament system in the nascent phase

Context. Star clusters, including high-mass stars, form within hub-filament systems (HFSs). Observations of HFSs that remain unaffected by feedback from embedded stars are rare yet crucial for understanding the mass inflow process in high-mass star formation. Using the JWST NIRCAM images, a recent study reported that the high-mass protostar G11P1 is embedded in a candidate HFS (G11P1-HFS; <0.6 pc). Aims. Utilizing ALMA N<inf>2</inf>H⁺(1–0) data, we confirm the presence of G11P1-HFS and study the dense gas kinematics. Methods. We analyzed the position–position–velocity (PPV) map and estimated on-sky velocity gradient (V<inf>g</inf>) and gravity (F<inf>g</inf>) vectors. We examined the spatial distribution of the gas velocity and the H<inf>2</inf> column density. Results. A steep V<inf>g</inf> of 5 km s⁻¹ pc⁻¹ and −7 km s⁻¹ pc⁻¹ toward either side of G11P1-hub and a decreasing V<inf>g</inf> toward the hub identify G11P1-HFS as a small-scale HFS in its nascent phase. Additionally, the V<inf>g</inf> and F<inf>g</inf> align along the filaments, indicating gravity-driven flows. Conclusions. This work highlights the wiggled funnel-shaped morphology of an HFS in PPV space and suggests the importance of sub-filaments or transverse gas flows in mass transportation to the hub.