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Related papers: Starless Cores

200 papers

The mass distributions of dense cores in star-forming regions are measured to have a shape similar to the initial mass function of stars. This has been generally interpreted to mean that the constituent cores will form individual stars or…

Astrophysics · Physics 2009-11-13 Jonathan J. Swift , Jonathan P. Williams

This paper will review the basic concepts of gas-phase and grain surface chemistry of dense molecular clouds, where low mass and high mass stars form. The chemistry of cold pre-stellar cloud cores, where molecular freeze-out and deuterium…

Astrophysics · Physics 2017-03-08 Paola Caselli

We present the chemistry, temperature, and dynamical state of a sample of 193 dense cores or core candidates in the Perseus Molecular cloud and compare the properties of cores associated with young stars and clusters with those which are…

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

Protostellar core formation is probably much more dynamic, and magnetic fields are probably much less important, than has been previously assumed in the standard model of low-mass star formation. This revised picture has important…

Astrophysics · Physics 2007-05-23 Lee Hartmann

The dense interiors of massive galaxies are among the most intriguing environments in the Universe. In this paper we ask when these dense cores were formed and determine how galaxies gradually assembled around them. We select galaxies that…

We construct models of molecular clouds that are considered as ensembles of transient cores. Each core is assumed to develop in the background gas of the cloud, grow to high density and decay into the background. The chemistry in each core…

Astrophysics · Physics 2009-11-13 R. T. Garrod , D. A. Williams , J. M. C. Rawlings

The Pipe nebula is a massive, nearby, filamentary dark molecular cloud with a low star-formation efficiency threaded by a uniform magnetic field perpendicular to its main axis. It harbors more than a hundred, mostly quiescent, very…

(Abridged) Context. Core condensation is a critical step in the star-formation process, but is still poorly characterized observationally. Aims. We have studied the 10 pc-long L1495/B213 complex in Taurus to investigate how dense cores have…

Astrophysics of Galaxies · Physics 2015-06-15 A. Hacar , M. Tafalla , J. Kauffmann , A. Kovacs

Young stars form on a wide range of scales, producing aggregates and clusters with various degrees of gravitational self-binding. The loose aggregates have a hierarchical structure in both space and time that resembles interstellar…

Astrophysics · Physics 2007-05-23 B. G. Elmegreen , Y. N. Efremov , R. E. Pudritz , H. Zinnecker

Star formation in strongly self-gravitating cloud cores should be similar at all redshifts, forming single or multiple stars with a range of masses determined by local magneto-hydrodynamics and gravity. The formation processes for these…

Astrophysics of Galaxies · Physics 2017-01-11 Bruce G. Elmegreen

Dust grains in neutral gas behave as aerodynamic particles, so they can develop large density fluctuations independent of gas density fluctuations. Specifically, gas turbulence can drive order-of-magnitude 'resonant' fluctuations in the…

Astrophysics of Galaxies · Physics 2015-12-15 Philip F. Hopkins

We discuss the observations and theory of star cluster formation to argue that clusters form dynamically cool (subvirial) and with substructure. We then perform an ensemble of simulations of cool, clumpy (fractal) clusters and show that…

Astrophysics of Galaxies · Physics 2009-07-22 R. J. Allison , S. P. Goodwin , R. J. Parker , R. de Grijs , S. F. Portegies Zwart , M. B. N. Kouwenhoven

We report the identification of a sample of potential High-Mass Starless Cores (HMSCs). The cores were discovered by comparing images of the fields containing candidate High-Mass Protostellar Objects (HMPOs) at 1.2mm and mid-infrared…

Astrophysics · Physics 2009-11-13 T. K. Sridharan , H. Beuther , M. Saito , F. Wyrowski , P. Schilke

The collapse of dense cores with different metallicities is studied by hydrodynamical calculations coupled with detailed chemical and radiative processes. For this purpose, we construct a simple chemical network with non-equilibrium…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Kazuyuki Omukai , Takashi Hosokawa , Naoki Yoshida

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

Cold molecular clouds are the birthplaces of stars and planets, where dense cores of gas collapse to form protostars. The dust mixed in these clouds is thought to be made of grains of an average size of 0.1 micrometer. We report the…

Astrophysics of Galaxies · Physics 2011-10-20 Laurent Pagani , Jürgen Steinacker , Aurore Bacmann , Amelia Stutz , Thomas Henning

(Abridged) Aims. We intend to derive statistical properties of stochastic gas motion inside the dense low mass star forming molecular cores traced by NH3(1,1) and (2,2) emission lines. Methods. We use the spatial two-point autocorrelation…

Astrophysics of Galaxies · Physics 2015-06-19 S. A. Levshakov , C. Henkel , D. Reimers , M. Wang

We summarize some of the results obtained from Herschel surveys of the nearby star forming regions and the Galactic plane. We show that in the nearby star forming regions the starless core spatial surface density distribution is very…

Astrophysics of Galaxies · Physics 2015-06-12 Leonardo Testi , Eli Bressert , S. Longmore

Sulfur is one of the most abundant elements in the Universe, yet the sulfur budget inferred from the observed sulfur-bearing molecules in dense cores is significantly lower than expected. Starless and pre-stellar cores represent the…

Astrophysics of Galaxies · Physics 2026-05-14 L. Schöller , S. Spezzano , O. Sipilä , E. I. Makarenko , P. Caselli , H. A. Bunn , S. S. Jensen