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Related papers: Molecular Cloud Fragmentation and Core Collapse

200 papers

Magnetic fields are believed to play an important role in the evolution of molecular clouds, from their large scale structure to dense cores, protostellar envelopes, and protoplanetary disks. How important is unclear, and whether magnetic…

Astrophysics · Physics 2007-05-23 Tyler L. Bourke , Alyssa A. Goodman

Molecular clouds, the birthplaces of stars in galaxies, form dynamically from the diffuse atomic gas of the interstellar medium (ISM). The ISM is also threaded by magnetic fields which have a large impact on its dynamics. In particular,…

Astrophysics of Galaxies · Physics 2015-09-14 Robi Banerjee , Bastian Körtgen

Star formation is inefficient. Recent advances in numerical simulations and theoretical models of molecular clouds show that the combined effects of interstellar turbulence, magnetic fields and stellar feedback can explain the low…

Solar and Stellar Astrophysics · Physics 2020-02-12 Christoph Federrath

We discuss the lifetimes and evolution of clumps and cores formed as turbulent density fluctuations in nearly isothermal molecular clouds. In the non-magnetic case, clumps are unlikely to reach a hydrostatic state, and instead are expected…

A cloud of gas collapsing under gravity will fragment. We present a new theory for this process, in which layers shocked gas fragment due to their gravitational instability. Our model explains why angular momentum does not inhibit the…

Astrophysics · Physics 2011-04-28 M. Wilkinson , B. Mehlig , M. A. Morgan

We present a detailed computational study of the assembly of protostellar disks and massive stars in molecular clouds with supersonic turbulence. We follow the evolution of large scale filamentary structures in a cluster-forming clump down…

Astrophysics · Physics 2009-11-11 Robi Banerjee , Ralph E. Pudritz , Dave W. Anderson

Gravitational collapse of the cylindrical elongated cloud is studied by numerical magnetohydrodynamical simulations. In the infinitely long cloud in hydrostatic configuration, small perturbations grow by the gravitational instability. The…

Astrophysics · Physics 2009-10-22 Kohji Tomisaka

Stars form from dense cores in turbulent molecular clouds. According to the standard scenario of star formation, dense cores are created by cloud fragmentation. However, the physical mechanisms driving this process are still not fully…

Astrophysics of Galaxies · Physics 2025-03-11 Kousuke Ishihara , Fumitaka Nakamura , Patricio Sanhueza , Masao Saito

(Abridged) In this review we focus on the observations and theory of the formation of early disks and outflows, and their connections with the first phases of planet formation. Large rotationally supported circumstellar disks, although…

Solar and Stellar Astrophysics · Physics 2015-06-18 Zhi-Yun Li , Robi Banerjee , Ralph E. Pudritz , Jes K. Jørgensen , Hsien Shang , Ruben Krasnopolsky , Anaëlle Maury

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov

Truncated abstract: The formation of a protostellar disc is a natural outcome during the star formation process. As gas in a molecular cloud core collapses under self-gravity, the angular momentum of the gas will slow its collapse on small…

Solar and Stellar Astrophysics · Physics 2018-12-18 James Wurster , Zhi-Yun Li

We analyse extinction maps of nearby Giant Molecular Clouds to forge a link between driving processes of turbulence and modes of star formation. Our investigation focuses on cloud structure in the column density range above the self…

Astrophysics of Galaxies · Physics 2015-05-28 J. Rowles , D. Froebrich

Filamentary molecular clouds are regarded as the place where newborn stars are formed. In particular, a hub region, a place where it appears as if several filaments are colliding, often indicates active star formation. To understand the…

Astrophysics of Galaxies · Physics 2023-09-06 Raiga Kashiwagi , Kazunari Iwasaki , Kohji Tomisaka

Context: The chemical composition of a molecular cloud changes dramatically as it collapses to form a low-mass protostar and circumstellar disk. Two-dimensional (2D) chemodynamical models are required to properly study this process. Aims:…

Astrophysics of Galaxies · Physics 2015-05-30 R. Visser , S. D. Doty , E. F. van Dishoeck

Molecular hydrogen (H$_2$) formation and dissociation are key processes that drive the gas lifecycle in galaxies. Using the SImulating the LifeCycle of Molecular Clouds (SILCC) zoom-in simulation suite, we explore the utility of future…

The study of the development of structures on multiple scales in the cold interstellar medium has experienced rapid expansion in the past decade, on both the observational and the theoretical front. Spectral line studies at (sub-)millimeter…

Observations indicate that dense molecular filamentary clouds are sites of star formation. The filament width determines the most unstable scale for self-gravitational fragmentation and influences the stellar mass. Therefore, constraining…

Astrophysics of Galaxies · Physics 2025-05-09 Daisei Abe , Tsuyoshi Inoue , Shu-ichiro Inutsuka , Doris Arzoumanian

In this paper we study the process of the subsequent (runaway) fragmentation of the rotating isothermal Giant Molecular Cloud (GMC) complex. Our own developed Smoothed Particle Hydrodynamics (SPH) gas-dynamical model successfully reproduce…

Astrophysics · Physics 2007-05-23 P. Berczik , M. I. Petrov

We present some important conclusions from recent calculations pertaining to the collapse of rotating molecular cloud cores with axial symmetry, corresponding to evolution of young stellar objects through classes 0 and begin of class I.…

Solar and Stellar Astrophysics · Physics 2015-05-13 W. M. Tscharnuter , J. Schönke , H. -P. Gail , E. Lüttjohann

Super-sonic turbulence fragments molecular clouds (MC) into a very complex density field with density contrasts of several orders of magnitude. A fraction of the gas is locked into dense and gravitationally bound cores, which collapse as…

Astrophysics · Physics 2007-05-23 Paolo Padoan , AAke Nordlund , Ornolfur Einar Rognvaldsson , Alyssa Goodman