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Related papers: Thermal structure of a protostellar envelope

200 papers

We study the formation and evolution of several molecules in a collapsing interstellar cloud using a reasonably large reaction network containing more then four hundred atomic and molecular species. We employ a time dependent, spherically…

Astrophysics · Physics 2009-06-30 Ankan Das , Sandip Kumar Chakrabarti , Kinsuk Acharyya , Sonali Chakrabarti

Convection is the most important physical process that determines the structure of the envelopes of cool stars. It influences the surface radiation flux and the shape of observed spectral line profiles and is responsible for both generating…

Solar and Stellar Astrophysics · Physics 2009-12-03 F. Kupka

Context. Clumping is a common property of stellar winds and is being incorporated to a solution of the radiative transfer equation coupled with kinetic equilibrium equations. However, in static hot model atmospheres, clumping and its…

Solar and Stellar Astrophysics · Physics 2021-11-10 Jiří Kubát , Brankica Kubátová

We have computed the dust temperature distribution to be expected in a pre-protostellar core in the phase prior to the onset of gravitational instability. We have done this in the approximation that the heating of the dust grains is solely…

Astrophysics · Physics 2009-11-06 A. Zucconi , C. M. Walmsley , D. Galli

We present an investigation on effect of the ion-neutral (or ambipolar) diffusion heating rate on thermal phases of a molecular cloud. We use the modeling of ambipolar diffusion with two-fluid smoothed particle hydrodynamics, as discussed…

Astrophysics · Physics 2008-04-29 M. Nejad-Asghar , D. Molteni

We re-examine the thermal evolution of the postshock layer in primordial gas clouds. Comparing the time scales, we find that the evolutionary paths of postshock regions in primordial gas clouds can be basically understood in terms of the…

Astrophysics · Physics 2009-10-30 Hajime Susa , Ryoichi Nishi , Hideya Uehara , Masako Yamada

In star forming regions, we can observe different evolutionary stages of various objects and phenomena such as molecular clouds, protostellar jets and outflows, circumstellar disks, and protostars. However, it is difficult to directly…

Solar and Stellar Astrophysics · Physics 2015-05-19 Masahiro N. Machida

Circumstellar disks of gas and dust are naturally formed from contracting pre-stellar molecular cores during the star formation process. To study various dynamical and chemical processes that take place in circumstellar disks prior to their…

Astrophysics of Galaxies · Physics 2017-09-27 Eduard I. Vorobyov , Yaroslav N. Pavlyuchenkov

Aims: We explore the long-term evolution of young protoplanetary disks with different approaches to computing the thermal structure determined by various cooling and heating processes in the disk and its surroundings. Methods: Numerical…

Earth and Planetary Astrophysics · Physics 2020-07-01 Eduard I. Vorobyov , Ryoki Matsukoba , Kazuyuki Omukai , Manuel Guedel

Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular…

Astrophysics · Physics 2007-05-23 Tom Abel , Greg L. Bryan , Michael L. Norman

The process of galaxy cluster formation likely leaves an imprint on the properties of its individual member galaxies. Understanding this process is essential for uncovering the evolutionary connections between galaxies and cosmic…

Sheet-like clouds are common in turbulent gas and perhaps form via collisions between turbulent gas flows. Having examined the evolution of an isothermal shocked slab in an earlier contribution, in this work we follow the evolution of a…

Astrophysics of Galaxies · Physics 2015-06-23 S. Anathpindika

Studies of the evolution of massive protostars and the evolution of their host molecular cloud cores are commonly treated as separate problems. However, interdependencies between the two can be significant. Here, we study the simultaneous…

Solar and Stellar Astrophysics · Physics 2015-06-16 Rolf Kuiper , Harold W. Yorke

Understanding the collapse of dense molecular cloud cores to stellar densities and the subsequent evolution of the protostar is of importance to model the feedback effects such an object has on its surrounding environment, as well as…

Solar and Stellar Astrophysics · Physics 2023-12-06 Adnan Ali Ahmad , Matthias González , Patrick Hennebelle , Benoît Commerçon

We review recent advances in the analytical and numerical modeling of the star formation rate in molecular clouds and discuss the available observational constraints. We focus on molecular clouds as the fundamental star formation sites,…

The structure of cloud complexes appears to be well described by a "tree structure" representation when the image is partitioned into "clouds". In this representation, the parent-child relationships are assigned according to containment.…

Astrophysics · Physics 2007-05-23 Nestor Sanchez , Antonio Parravano

We present a model for describing the general structure of molecular clouds (MCs) at early evolutionary stages in terms of their mass-size relationship. Sizes are defined through threshold levels at which equipartitions between…

Astrophysics of Galaxies · Physics 2016-04-26 Todor V. Veltchev , Sava Donkov , Ralf S. Klessen

We present PPMAP, a Bayesian procedure that uses images of dust continuum emission at multiple wavelengths to produce resolution-enhanced image cubes of differential column-density as a function of dust temperature and position. PPMAP is…

Instrumentation and Methods for Astrophysics · Physics 2015-11-04 K. A. Marsh , A. P. Whitworth , O. Lomax

We describe a comprehensive model for the formation and morphological development of atmospheric ice crystals growing from water vapor, also known as snow crystals. Our model derives in part from empirical measurements of the intrinsic ice…

Materials Science · Physics 2012-11-26 Kenneth G. Libbrecht

{It is well established that the atomic interstellar hydrogen is filling the galaxies and constitutes the building blocks of molecular clouds.} {To understand the formation and the evolution of molecular clouds, it is necessary to…

Astrophysics of Galaxies · Physics 2015-05-14 E. Audit , P. Hennebelle