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Related papers: Fractional Stars

200 papers

Gas processes affecting star formation are reviewed with an emphasis on gravitational and magnetic instabilities as a source of turbulence. Gravitational instabilities are pervasive in a multi-phase medium, even for sub-threshold column…

Astrophysics · Physics 2008-11-26 Bruce G. Elmegreen

Turbulence is thought to be a primary driving force behind the early stages of star formation. In this framework large, self gravitating, turbulent clouds fragment into smaller clouds which in turn fragment into even smaller ones. At the…

Solar and Stellar Astrophysics · Physics 2016-03-17 David Guszejnov , Philip F. Hopkins

Observations suggest that star formation occurs in only one or two crossing times for a range of scales spanning a factor of 1000. These observations include (1) measurements of embedded cluster ages in comparison with the cloud core…

Astrophysics · Physics 2009-10-31 Bruce G. Elmegreen

We review current understanding of star formation, outlining an overall theoretical framework and the observations that motivate it. A conception of star formation has emerged in which turbulence plays a dual role, both creating…

Astrophysics · Physics 2008-11-26 Christopher F. McKee , Eve C. Ostriker

We study the effect of varying the equation of state on the formation of stellar clusters in turbulent molecular clouds, using three-dimensional, smoothed particle hydrodynamics simulations. Our results show that the equation of state helps…

Astrophysics · Physics 2015-06-24 Yuexing Li , Ralf S. Klessen , Mordecai-Mark Mac Low

We examine the effects of $f(R)$ gravity on Jeans analysis of collapsing dust clouds. We provide a method for testing modified gravity models by their effects on star formation as the presence of $f(R)$ gravity is found to modify the limit…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-06 Jaakko Vainio , Iiro Vilja

During the last two decades, the focus of star formation research has shifted from understanding the collapse of a single dense core into a star to studying the formation hundreds to thousands of stars in molecular clouds. In this chapter,…

Astrophysics · Physics 2008-01-04 S. T. Megeath , Zhi-Yun Li , Aake Nordlund

Understanding star formation is problematic as it originates in the large scale dynamics of a galaxy but occurs on the small scale of an individual star forming event. This paper presents the first numerical simulations to resolve the star…

Astrophysics of Galaxies · Physics 2015-06-12 Ian A. Bonnell , Clare L. Dobbs , Rowan J. Smith

The relations between star formation and properties of molecular clouds are studied based on a sample of star forming regions in the Galactic Plane. Sources were selected by having radio recombination lines to provide identification of…

Solar and Stellar Astrophysics · Physics 2017-03-08 Nalin Vutisalchavakul , Neal J. Evans , Mark Heyer

The inner few hundred parsecs of the Milky Way harbours gas densities, pressures, velocity dispersions, an interstellar radiation field and a cosmic ray ionisation rate orders of magnitude higher than the disc; akin to the environment found…

Astrophysics of Galaxies · Physics 2017-06-21 A. T. Barnes , S. N. Longmore , C. Battersby , J. Bally , J. M. D. Kruijssen , J. D. Henshaw , D. L. Walker

Dust and gas energetics are incorporated into a cluster-scale simulation of star formation in order to study the effect of heating and cooling on the star formation process. We build on our previous work by calculating separately the dust…

Solar and Stellar Astrophysics · Physics 2015-06-05 Hugo Martel , Andrea Urban , Neal J. Evans

We review the main results from recent numerical simulations of turbulent fragmentation and star formation. Specifically, we discuss the observed scaling relationships, the ``quiescent'' (subsonic) nature of many star-forming cores, their…

Astrophysics · Physics 2008-11-26 Javier Ballesteros-Paredes

Stars are often observed to form in clusters. It is therefore important to understand how such a region of concentrated mass is assembled out of the diffuse medium and its properties eventually prescribe the important physical mechanisms…

Astrophysics of Galaxies · Physics 2016-06-08 Yueh-Ning Lee , Patrick Hennebelle

Most young stars in nearby molecular clouds have estimated ages of 1-2 Myr, suggesting that star formation is rapid. However, small numbers of stars in these regions with inferred ages of >= 5-10 Myr have been cited to argue that star…

Solar and Stellar Astrophysics · Physics 2015-06-03 Lee Hartmann , Javier Ballesteros-Paredes , Fabian Heitsch

Understanding the physics of how stars form is a highly-prioritized goal of modern Astrophysics, in part because star formation is linked to both galactic dynamics on large scales and to the formation of planets on small scales. It is…

Using a new physical model for star formation (Padoan 1995) we have tested the possibility that globular clusters (GCs) are formed from primordial mass fluctuations, whose mass scale ($10^8$ - $10^9$ M$_{\odot}$) is selected out of a CDM…

Astrophysics · Physics 2015-06-24 Paolo Padoan , Raul Jimenez , Bernard Jones

The thermal and chemical evolution of gravitationally collapsing protostellar clouds is investigated, focusing attention on their dependence on metallicity. Calculations are carried out for a range of metallicities spanning the local…

Astrophysics · Physics 2009-10-31 Kazuyuki Omukai

Over the last two decades, realistic studies have often concluded that the first bound objects to form can be very small, much smaller than a solar mass. After recombination, the Jeans mass drops rapidly to the order of a Giant Molecular…

Astrophysics · Physics 2007-05-23 F. Combes , D. Pfenniger

Here we model a star forming factory in which the continuous creation of stars results in a highly concentrated, massive (globular cluster-like) stellar system. We show that under very general conditions a large-scale gravitational…

We study gravitational instability and consequent star formation in a wide range of isolated disk galaxies, using three-dimensional, smoothed particle hydrodynamics simulations at resolution sufficient to fully resolve gravitational…

Astrophysics · Physics 2009-11-10 Yuexing Li , Mordecai-Mark Mac Low , Ralf S. Klessen