Discovery of a Rich Population of Compact Hub-filament Systems in a Single Star-forming Complex
Abstract
Abstract We report the discovery of 45 compact hub-filament systems (HFSs; median size ∼2.4 pc) in infrared-dark clouds (IRDCs) in the W33 complex, located at the junction of the Scutum and Norma spiral arms. Using Spitzer 8 and 24 µ m, and unWISE 12 μ m images, HFSs are identified as regions where three or more filaments converge onto a central hub, appearing as absorption features toward IRDCs. In each IRDC, HFSs mainly lie at the intersections of elongated substructures, associated with groups of protostars and lacking radio continuum emission. Minimum Spanning Tree (MST) analysis shows that protostars are closely associated with the HFSs, with protostellar core separations of ≤0.7 pc, indicating strong clustering within fragmented structures. The HFSs form two main groupings spanning 10–15 pc, with member separations of 1–3.3 pc. Around 65% are tightly clustered (
Fields of Study & Subjects
Astrophysics and Star Formation Studies
Astronomy and Astrophysical Research
Fullerene Chemistry and Applications
Publication details
- Journal / source
- The Astronomical Journal
- Publisher
- American Astronomical Society
- Volume
- 171
- Issue
- 2
- Pages
- 69–69
- Publication date
- 6 January 2026
- Language
- EN