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Related papers: Structure and Stability of Prestellar Cores

200 papers

We simulate the formation and collapse of prestellar cores at few-AU resolution in a set of radiation-magneto-hydrodynamic simulations of giant molecular clouds (GMCs) using the grid-based code RAMSES-RT. We adopt, for the first time to our…

Astrophysics of Galaxies · Physics 2023-05-10 Chong-Chong He , Massimo Ricotti

The turbulent motion within molecular clouds is a key factor controlling star formation. Turbulence supports molecular cloud cores from evolving to gravitational collapse and hence sets a lower bound on the size of molecular cloud cores in…

Solar and Stellar Astrophysics · Physics 2015-06-23 Yang Gao , Haitao Xu , Chung K. Law

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

We explore whether observed molecular clouds could include a substantial population of unbound clouds. Using simulations which include only turbulence and gravity, we are able to match observed relations and naturally reproduce the observed…

Astrophysics of Galaxies · Physics 2014-03-05 Rachel L. Ward , James Wadsley , Alison Sills

By minimizing free energy density, we show that the stellar core of a hydrogen burning star is not in a global thermodynamical equilibrium unless density, temperature, mass and composition assume given values. The core (as the solar…

Nuclear Theory · Physics 2009-11-11 F. Ferro , A. Lavagno , P. Quarati

In order to understand the origin of observed molecular cloud properties, it is critical to understand how clouds interact with their environments during their formation, growth, and collapse. It has been suggested that accretion-driven…

Astrophysics of Galaxies · Physics 2018-12-21 Juan C. Ibáñez-Mejía , Mordecai-Mark Mac Low , Ralf S. Klessen , Christian Baczynski

Stars form within molecular clouds but our understanding of this fundamental process remains hampered by the complexity of the physics that drives their evolution. We review our observational and theoretical knowledge of molecular clouds…

Astrophysics of Galaxies · Physics 2015-06-12 Patrick Hennebelle , Edith Falgarone

Molecular line observations of starless (prestellar) cores combined with a chemical evolution modeling and radiative transfer calculations are a powerful tool to study the earliest stages of star formation. However, conclusions drawn from…

Astrophysics · Physics 2009-11-13 Ya. Pavlyuchenkov , Th. Henning , D. Wiebe

We present the first systematic study of the density structure of clouds found in a complete sample covering all major molecular clouds in the Central Molecular Zone (CMZ; inner $\sim{}200~\rm{}pc$) of the Milky Way. This is made possible…

The efficiency of star formation, defined as the ratio of the stellar to total (gas and stellar) mass, is observed to vary from a few percent in regions of dispersed star formation to about a third in cluster-forming cores. This difference…

Astrophysics · Physics 2009-11-10 Fumitaka Nakamura , Zhi-Yun Li

Constraining the physical and chemical evolution of molecular clouds is essential to our understanding of star formation. These investigations often necessitate knowledge of some local representative number density of the gas along the line…

Astrophysics of Galaxies · Physics 2025-04-02 Brandt A. L. Gaches , Michael Y. Grudić

The formation of stars is inextricably linked to the structure of their parental molecular clouds. Here we take a number of nearby giant molecular clouds (GMCs) and analyse their column density and mass distributions. This investigation is…

Astrophysics of Galaxies · Physics 2015-05-18 D. Froebrich , J. Rowles

In a new simple model I reconcile two contradictory views on the factors that determine the rate at which molecular clouds form stars -- internal structure vs. external, environmental influences -- providing a unified picture for the…

Astrophysics of Galaxies · Physics 2016-02-17 Sharon E. Meidt

One of the key problems in star formation research is to determine the role of magnetic fields. Starting from the atomic inter-cloud medium (ICM) which has density nH ~ 1 per cubic cm, gas must accumulate from a volume several hundred pc…

Astrophysics of Galaxies · Physics 2015-05-13 Hua-bai Li , C. Darren Dowell , Alyssa Goodman , Roger Hildebrand , Giles Novak

Abridged. A large fraction of stars are found in binary systems. It is therefore important for our understanding of the star formation process, to investigate the fragmentation of dense molecular cores. We study the influence of the…

Astrophysics · Physics 2009-11-13 P. Hennebelle , R. Teyssier

We examine the role of the gravitational instability in an isothermal, self-gravitating layer threaded by magnetic fields on the formation of filaments and dense cores. Using numerical simulation we follow the non-linear evolution of a…

Solar and Stellar Astrophysics · Physics 2015-06-19 Sven Van Loo , Eric Keto , Qizhou Zhang

We present an analysis of the large-scale molecular cloud structure and of the stability of clumpy structures in nearby molecular clouds. In our recent work, we identified a structural transition in molecular clouds by studying the…

Astrophysics of Galaxies · Physics 2015-05-27 J. Kainulainen , H. Beuther , R. Banerjee , C. Federrath , T. Henning

The density of cosmic rays inside molecular clouds determines the ionization rate in the dense cores where stars form. It is also one of the drivers of astrochemistry leading to the creation of complex molecules. Through Fermi Large Area…

High Energy Astrophysical Phenomena · Physics 2023-01-18 Rui-zhi Yang , Guang-Xing Li , Emma de Oña Wilhelmi , Yu-Dong Cui , Bing Liu , Felix Aharonian

(Abridged) In this paper, we present analyses of images taken with the Herschel ESA satellite from 70mu to 500mu. We first constructed column density and dust temperature maps. Next, we identified compact cores in the maps, and characterize…

Molecular gas disks are generally Toomre stable ($Q_T>$1) and yet clearly gravitationally unstable to structure formation as evidenced by the existence of molecular clouds and ongoing star formation. This paper adopts a 3D perspective to…

Astrophysics of Galaxies · Physics 2022-10-12 Sharon E. Meidt