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Related papers: An analytic column density profile to fit prestell…

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(Abrigded) We discuss the column density profiles of "cores" in 3D SPH numerical simulations of turbulent molecular clouds. The SPH scheme allows us to perform a high spatial resolution analysis of the density maxima (cores) at scales…

The gravitational collapse of a spherical cloud core is investigated by numerical calculations. The initial conditions of the core lie close to the critical Bonnor-Ebert sphere with a central density of \sim 10^4 cm^{-3} in one model…

Astrophysics · Physics 2009-11-10 Yuri Aikawa , Eric Herbst , Helen Roberts , Paola Caselli

Radial density profiles for the sample of dense cores associated with high-mass star-forming regions from southern hemisphere have been derived using the data of observations in continuum at 250 GHz. Radial density profiles for the inner…

Astrophysics of Galaxies · Physics 2014-11-20 Lev E. Pirogov

Utilizing multi-wavelength dust emission maps acquired with $Herschel$, we reconstruct local volume density and dust temperature profiles for the prestellar cores B68 and L1689B using inverse-Abel transform based technique. We present…

We have modeled the emission from dust in pre-protostellar cores, including a self-consistent calculation of the temperature distribution for each input density distribution. Model density distributions include Bonnor-Ebert spheres and…

Astrophysics · Physics 2009-11-06 Neal J. Evans , Jonathan M. C. Rawlings , Yancy L. Shirley , Lee G. Mundy

We propose a simple analytical method for estimating the central volume density of prestellar molecular cloud cores from their column density profiles. Prestellar cores feature a flat central part of the column density and volume density…

Astrophysics of Galaxies · Physics 2015-05-28 Konstantinos Tassis , Harold W. Yorke

Short version: We apply a new synergetic radiative transfer method: the derived 1D density profiles are both consistent with a cut through the Herschel PACS/SPIRE and JCMT SCUBA-2 continuum maps of L1689B and with a derived local…

Astrophysics of Galaxies · Physics 2016-09-07 Juergen Steinacker , Aurore Bacmann , Thomas Henning , Stefan Heigl

We present a near-infrared extinction study of the dark globule L694-2, a starless core that shows strong evidence for inward motions in molecular line profiles. The J,H, and K band data were taken using the European Southern Observatory…

We have considered the thermal equilibrium in pre-protostellar cores in the approximation where the dust temperature is independent of interactions with the gas and where the gas is heated both by collisions with dust grains and ionization…

Astrophysics · Physics 2009-11-07 D. Galli , M. Walmsley , J. Goncalves

Observations have been carried out with SCUBA at the JCMT of 52 molecular cloud cores that do not contain any sign of protostellar activity. These are all therefore candidate prestellar cores, which are believed to represent the stage of…

Astrophysics · Physics 2009-11-11 J. M. Kirk , D. Ward-Thompson , P. André

We have investigated the physical and chemical status of the pre-protostellar core B68. A previous extinction study suggested that the density profile of B68 is remarkably consistent with a Bonnor-Ebert sphere with 2.1 $M_{\odot}$ at 16 K.…

Astrophysics · Physics 2009-11-07 Shih-Ping Lai , T. Velusamy , W. D. Langer , T. B. H. Kuiper

Starless cores represent the initial stage of evolution toward (proto)star formation, and a subset of them, known as prestellar cores, with high density (~ 10^6 cm^-3 or higher) and being centrally concentrated are expected to be embryos of…

We present a catalogue of molecular cloud cores drawn from high latitude, medium opacity clouds, using the all-sky IRAS Sky Survey Atlas (ISSA) images at 60 and 100~$\mu$m. The typical column densities of the cores are $ N(H_2)\sim 3.8…

Astrophysics · Physics 2009-10-31 N. E. Jessop , D. Ward-Thompson

Models of self-gravitating gas in the early stages of pressure-free collapse are compared for initial states which are equilibrium layers, cylinders, and Bonnor-Ebert spheres. For each geometrical case the density profile has an inner…

Astrophysics · Physics 2009-11-10 Philip C. Myers

We present a near-infrared extinction study of the dark globule B335, a protostellar collapse candidate, using data from HST/NICMOS and the W.M. Keck Observatory. These data allow a new quantitative test of the "inside-out" collapse model…

(Abridged) We present numerical hydrodynamical simulations of the formation, evolution and gravitational collapse of isothermal molecular cloud cores. A compressive wave is set up in a constant sub-Jeans density distribution of radius r = 1…

We present a detailed study of the collapse of molecular cloud cores using high resolution 3D adaptive mesh refinement (AMR) numerical simulations. In this first in a series of investigations our initial conditions consists of spherical…

Astrophysics · Physics 2009-11-10 Robi Banerjee , Ralph E. Pudritz , Lindsay Holmes

Aims: We aim to derive a stability condition for non-isothermal Bonnor-Ebert spheres and compare the physical properties of critical non-isothermal and isothermal gas spheres. These configurations can serve as models for prestellar cores…

Astrophysics of Galaxies · Physics 2015-05-30 O. Sipilä , J. Harju , M. Juvela

We present a detailed study of the Orion B clouds (d~400 pc), imaged with the PACS/SPIRE cameras at 70-500 $\mu$m by the Herschel Gould Belt survey (HGBS). We release new high-res. maps of column density and dust temperature. In the…

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