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Related papers: Prolate Cores in Filamentary Molecular Clouds

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We study the rotational properties of magnetized and self-gravitating molecular cloud cores formed in 2 very high resolution 3D molecular cloud simulations.The simulations have been performed using the code RAMSES at an effective resolution…

We investigate the collapse and fragmentation of low-mass, trans-sonically turbulent prestellar cores, using SPH simulations. The initial conditions are slightly supercritical Bonnor-Ebert spheres, all with the same density profile, the…

Solar and Stellar Astrophysics · Physics 2015-05-13 S. Walch , T. Naab , A. Burkert , A. Whitworth , M. Gritschneder

Filamentary structures are widely observed in molecular clouds, yet most filament observations are biased toward case studies and small samples; a uniform census within a single giant molecular cloud is still missing. We do a complete…

Astrophysics of Galaxies · Physics 2026-03-18 Yingxi Li , Keping Qiu

Emission line profiles of tracer molecule H$_2$CO 140 GHz transition from gravitational core collapsing clouds in the dynamic process of forming protostars are calculated, using a simple ray-tracing radiative transfer model. Three…

Solar and Stellar Astrophysics · Physics 2015-05-13 Yang Gao , Yu-Qing Lou , Kinwah Wu

Two scenarios have been proposed for evolution of star forming cores: gravitational fragmentation of larger structures and coalescence of smaller entities which are formed from some instabilities. Here, we turn our attention to the latter…

Astrophysics of Galaxies · Physics 2015-05-18 M. Nejad-Asghar

We present results from radiation non-ideal magnetohydrodynamics (MHD) calculations that follow the collapse of rotating, magnetised, molecular cloud cores to stellar densities. These are the first such calculations to include all three…

Solar and Stellar Astrophysics · Physics 2018-02-07 James Wurster , Matthew R. Bate , Daniel J. Price

We present a new analytical three-parameter formula to fit observed column density profiles of prestellar cores. It represents a line-of-sight integral through a spherically symmetric or disc-like isothermal cloud. The underlying model…

Solar and Stellar Astrophysics · Physics 2013-08-19 Wolf B. Dapp , Shantanu Basu

We present results from the first three-dimensional calculations ever to follow the collapse of a molecular cloud core (~ 10^{-18} g cm^{-3}) to stellar densities (> 0.01 g cm^{-3}). The calculations resolve structures over 7 orders of…

Astrophysics · Physics 2009-10-31 Matthew R. Bate

Dense molecular filaments are central to the star formation process, but the detailed manner in which they fragment into prestellar cores is not yet well understood. Here, we investigate the fragmentation properties and dynamical state of…

Solar and Stellar Astrophysics · Physics 2020-10-07 Guo Yin Zhang , Ph. Andre , A. Menshchikov , Ke Wang

We study numerically the collapse of rotating, magnetized molecular cloud cores, focusing on rotation and magnetic braking during the main accretion phase of isolated star formation. Motivated by previous numerical work and analytic…

Astrophysics · Physics 2009-11-10 A. Allen , Z. Y. Li , F. H. Shu

We study effect of magnetic field on massive dense core formation in colliding unequal molecular clouds by performing magnetohydrodynamic simulations with sub-parsec resolution (0.015 pc) that can resolve the molecular cores. Initial clouds…

Astrophysics of Galaxies · Physics 2020-07-23 Nirmit Sakre , Asao Habe , Alex R. Pettitt , Takashi Okamoto

Observations of magnetic field strengths imply that molecular cloud fragments are individually close to being in a magnetically critical state, even though both magnetic field and column density measurements range over two orders of…

Astrophysics · Physics 2007-05-23 Shantanu Basu

The Orion A molecular cloud is one of the most well-studied nearby star-forming regions, and includes regions of both highly clustered and more dispersed star formation across its full extent. Here, we analyze dense, star-forming cores…

We present the results of a suite of numerical simulations designed to explore the origin of the angular momenta of protostellar cores. Using the hydrodynamic grid code \emph{Athena} with a sink implementation, we follow the formation of…

Solar and Stellar Astrophysics · Physics 2019-05-08 Aleksandra Kuznetsova , Lee Hartmann , Fabian Heitsch

Magnetic fields are important contributers to the dynamics of collapsing molecular cloud cores, and can have a major effect on whether collapse results in a single protostar or fragmentation into a binary or multiple protostar system. New…

Solar and Stellar Astrophysics · Physics 2015-06-12 Alan P. Boss , Sandra A. Keiser

This is the first paper about the fragmentation and mass outflow in the molecular cloud by using three-dimensional MHD nested-grid simulations. The binary star formation process is studied paying particular attention to the fragmentation of…

Astrophysics · Physics 2009-11-10 Masahiro N Machida , Kohji Tomisaka , Tomoaki Matsumoto

In this study, we investigate the shapes of starless and protostellar cores using hydrodynamic, self-gravitating adaptive mesh refinement simulations of turbulent molecular clouds. We simulate observations of these cores in dust emission,…

Astrophysics · Physics 2011-02-11 S. S. R. Offner , M. R. Krumholz

The mass distribution of prestellar cores is obtained for clouds with arbitrary internal mass distributions using a selection criterion based on the thermal and turbulent Jeans mass and applied hierarchically from small to large scales. We…

Solar and Stellar Astrophysics · Physics 2012-08-02 Antonio Parravano , Nestor Sanchez , Emilio J. Alfaro

Using the imaging polarimeter for the Submillimeter Common User Bolometric Array at the James Clerk Maxwell Telescope, we have detected polarized thermal emission at 850 micron from dust toward three star-forming core systems in the Orion B…

Astrophysics · Physics 2009-11-07 B. C. Matthews , J. D. Fiege , G. H. Moriarty-Schieven

We present an idealized, spherical model of the evolution of a magnetized molecular cloud due to ambipolar diffusion. This model allows us to follow the quasi-static evolution of the cloud's core prior to collapse and the subsequent…

Astrophysics · Physics 2009-10-30 P. N. Safier , C. F. McKee , S. W. Stahler