Work

A Pan-galaxy Study of Synthetic Giant Molecular Filaments: A Turbulence-dominated Life Cycle

Year: 2026

Type: article

Abstract: Recent surveys of the Galactic plane have revealed dozens of giant molecular filaments (GMFs), with lengths ranging from tens to hundreds of parsecs, yet their origins and life cycles remain debated. In this work, we analyze over 700 GMFs identified from synthetic CO emission maps of a high-resolution magnetohydrodynamic simulation of a Milky Way–like galaxy, whose lengths range from ∼10 to ∼300 pc. We find that turbulent shock from galactic shear and stellar feedback are the primary drivers of GMF formation. Magnetized turbulence dominates their internal dynamics, supporting the filaments against global collapse while simultaneously inducing fragmentation into dense clumps. This fragmentation follows the turbulence-driven sausage instability model, rather than pure Jeans instability, and triggers efficient star formation along the filaments. Cloud–cloud collisions are frequent, affecting more than 70% of GMFs, and often disrupt or reshape their morphology. The typical filamentary lifetime is t fil = 1 4 − 5 + 2 Myr, comparable to the crossing time of giant molecular clouds (GMCs). The molecular gas half-life is ∼7 Myr, similar to that of GMCs, indicating that GMFs are transient but dynamically important structures.

Source: The Astrophysical Journal Supplement Series

DOI: 10.3847/1538-4365/ae2a21

Authors: Zipeng Hu, Ke Wang, Mark R. Krumholz, Keyun Su

Institutions: Peking University, Australian National University

Language: English

Topic: Astrophysics and Star Formation Studies

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $4,499

Funders: National Computational Infrastructure, Australian Government, National Natural Science Foundation of China, Peking University