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Related papers: Structure and Stability of Prestellar Cores

200 papers

We review the progress that has been made in observing and analyzing molecular cloud structure in recent years. Structures are self-similar over a wide range of scales with similar power law indices independent of the star forming nature of…

Astrophysics · Physics 2007-05-23 Jonathan P. Williams , Leo Blitz , Christopher F. McKee

Understanding the physical properties of star-forming cores as mass reservoirs for protostars, and the impact of turbulence, is crucial in star formation studies. We implemented passive tracer particles in clump-scale numerical simulations…

Astrophysics of Galaxies · Physics 2025-01-08 Shingo Nozaki , Hajime Fukushima , Kazuki Tokuda , Masahiro N. Machida

Molecular clouds are supported by thermal pressure, magnetic pressure, and turbulent pressure. Each of these can be modeled with a polytropic equation of state, so that overall the total pressure is the sum of the individual components. We…

Astrophysics · Physics 2012-08-27 Christopher F. McKee , John H. Holliman , II

We carry out three-dimensional MHD simulations of star formation in turbulent, magnetized clouds, including ambipolar diffusion and feedback from protostellar outflows. The calculations focus on relatively diffuse clouds threaded by a…

Astrophysics · Physics 2009-11-13 Fumitaka Nakamura , Zhi-Yun Li

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

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…

We examine the linear stability of a filamentary cloud permeated by a perpendicular magnetic field. The initial magnetic field is assumed to be uniform and perpendicular to the cloud axis. The model cloud is assumed to have a Plummer-like…

Astrophysics of Galaxies · Physics 2019-09-04 Tomoyuki Hanawa , Takahiro Kudoh , Kohji Tomisaka

We use magnetohydrodynamical simulations of converging flows to investigate the process of molecular cloud formation and evolution out of the magnetised ISM. Here, we investigate whether the observed subcritical HI clouds can become…

Astrophysics of Galaxies · Physics 2015-06-02 Bastian Körtgen , Robi Banerjee

Magnetic fields are believed to play an important role in controlling the stability and contraction of dense condensations of gas and dust leading to the formation of stars and planetary systems. In the present study, the magnetic field of…

The initial and boundary conditions of the Galactic star formation in molecular clouds are not well understood. In an effort to shed new light on this long-standing problem, we measured properties of dense cores and filamentary structures…

Astrophysics of Galaxies · Physics 2023-06-28 Xue-Mei Li , Guo-Yin Zhang , Alexander Men'shchikov , Jin-Zeng Li , Chang Zhang , Zhong-Zu Wu

Molecular-line observations of star-forming cloud cores indicate that they are not the flattened structures traditionally considered by theory. Rather, they are elongated, perhaps in the direction of their internal magnetic field. We are…

Astrophysics · Physics 2009-11-06 Charles L. Curry , Steven W. Stahler

We investigate the uncertainties affecting the temperature profiles of dense cores of interstellar clouds. In regions shielded from external ultraviolet radiation, the problem is reduced to the balance between cosmic ray heating, line…

Astrophysics of Galaxies · Physics 2015-05-30 M. Juvela , N. Ysard

We study the formation, evolution and collapse of dense cores by tracking structures in a magnetohydrodynamic simulation of a star-forming cloud. We identify cores using the dendrogram algorithm and utilize machine learning techniques,…

We utilize the more than 100 gravitationally-bound dense cores formed in our three-dimensional, turbulent MHD simulations reported in Chen & Ostriker (2015) to analyze structural, kinematic, and magnetic properties of prestellar cores. Our…

Solar and Stellar Astrophysics · Physics 2018-10-10 Che-Yu Chen , Eve C. Ostriker

We aim at characterising dense cores in the clustered environments associated with massive star-forming regions. For this, we present an uniform analysis of VLA NH3(1,1) and (2,2) observations towards a sample of 15 massive star-forming…

In this study we investigate the formation and properties of prestellar and protostellar cores using hydrodynamic, self-gravitating Adaptive Mesh Refinement simulations, comparing the cases where turbulence is continually driven and where…

Astrophysics · Physics 2009-11-13 S. S. R. Offner , M. R. Krumholz , R. I. Klein , C. F. McKee

Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of resulting star and planetary systems. Here we study the role of pressure, parameterized via ambient clump mass surface…

Astrophysics of Galaxies · Physics 2015-06-23 Yichen Zhang , Jonathan C. Tan

Recent dust continuum surveys have shown that filamentary structures are ubiquitous along the Galactic plane. While the study of their global properties has gained momentum recently, we are still far from fully understanding their origin…

Astrophysics of Galaxies · Physics 2015-06-16 Yanett Contreras , Jill Rathborne , Guido Garay

We follow the ambipolar-diffusion--driven formation and evolution of a fragment in a magnetically supported molecular cloud, until a hydrostatic protostellar core forms at its center. This problem was formulated in Paper I. We determine the…

Astrophysics · Physics 2011-02-11 Konstantinos Tassis , Telemachos Ch. Mouschovias

A physical model and two-dimensional numerical method for computing the evolution and spectra of protostellar clouds are described. The physical model is based on a system of magneto-gasdynamical equations, including ohmic and ambipolar…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. G. Zhilkin , Ya. N. Pavlyuchenkov , S. N. Zamozdra