The Thermal Structure of a Protostellar Envelope

Autor(en)
Yaroslav Pavlyuchenkov, Andrey Zhilkin, Eduard Vorobiev, A. M. Fateeva
Abstrakt

A numerical hydrodynamical model for the evolution of spherically symmetric collapsing clouds, designed for the calculation of the thermal structure of these objects in both the prestellar and protostellar stages of their evolution, is presented. Distinctive features of the model include the possibility of independently describing the temperatures of the gas and dust, which is extremely important when calculating the thermal structure of prestellar and protostellar clouds, and the account of the radiation flux from the central protostar. This model is used to compare the theoretical density and temperature distributions with observations for nearby sites of star formation obtained with the Herschel Space Observatory. Application of the diffusion approximation with a flux limiter describes well the radial density and temperature distributions in protostellar clouds. However, significant differences between the model and observational density profiles were found for prestellar stages, suggesting the presence of appreciable deviations from equilibrium in the prestellar clouds. An approximate method for calculating the thermal structure of a cloud based on the adaptive τ-approximation is presented. Application of the τ-approximation yields good agreement with the diffusion approximation for the prestellar phase, but produces appreciable discrepancies for the protostellar phase, when the thermal structure of the accreting envelope is determined by the radiation of the protostar.

Organisation(en)
Institut für Astrophysik
Externe Organisation(en)
Russian Academy of Sciences, Chelyabinsk State University, Southern Federal University
Journal
Astronomy Reports
Band
59
Seiten
133-144
Anzahl der Seiten
12
ISSN
1063-7729
DOI
https://doi.org/10.1134/S1063772915020067
Publikationsdatum
02-2015
Peer-reviewed
Ja
ÖFOS 2012
103003 Astronomie, 103004 Astrophysik
Schlagwörter
ASJC Scopus Sachgebiete
Astronomy and Astrophysics, Space and Planetary Science
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/the-thermal-structure-of-a-protostellar-envelope(ef230b80-5dde-4a50-b84c-0db9c8a4cafc).html