2005/07/24 by Fabian Heitsch, F. Heitsch, Andreas Burkert +7 · 3 citations
Chemical Engineering · Earth and Planetary Sciences · Physics and Astronomy · #Advanced Combustion Engine Technologies #Astrophysics #Astrophysics and Star Formation Studies #Atmospheric Ozone and Climate #Chemical physics #Classical mechanics #Flow (mathematics) #Galaxy #Gravitation #Gravitational collapse #Hydrogen #Mechanics #Meteorology #Molecular cloud #Nonlinear system #Physics #Quantum mechanics #Star formation #Stars #Structure formation #Thermal #Turbulence #astro-ph
paper · pdf · doi:10.1086/498413
published as Astrophys.J.633:L113-L116,2005 · 4 pages, 5 figures, resubmitted to ApJL
arxiv created 2005/07/24 · openalex publication_date 2005/10/26 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Molecular clouds (MCs) are highly structured and turbulent. Colliding gas streams of atomic hydrogen have been suggested as a possible source of MCs, imprinting the filamentary structure as a consequence of dynamical and thermal instabilities. We present a two-dimensional numerical analysis of MC formation via converging H I flows. Even with modest flow speeds and completely uniform inflows, nonlinear density perturbations arise as possible precursors of MCs. Thus, we suggest that MCs are inevitably formed with substantial structure, e.g., strong density and velocity fluctuations, which provide the initial conditions for subsequent gravitational collapse and star formation in a variety of Galactic and extragalactic environments.