English
Related papers

Related papers: Do we need to know the temperature in prestellar c…

200 papers

Context. The different theoretical models concerning the formation of high-mass stars make distinct predictions regarding their progenitors, i.e. the high-mass prestellar cores. However, so far no conclusive observation of such objects has…

Astrophysics of Galaxies · Physics 2021-06-30 E. Redaelli , S. Bovino , A. Giannetti , G. Sabatini , P. Caselli , F. Wyrowski , D. R. G. Schleicher , D. Colombo

Given the low ionization fraction of molecular clouds, ambipolar diffusion is thought to be an integral process in star formation. However, chemical and radiative-transfer effects, observational challenges, and the fact that the ion-neutral…

Astrophysics of Galaxies · Physics 2023-03-29 Aris Tritsis , Shantanu Basu , Christoph Federrath

For a number of starless cores, self-absorbed molecular line and column density observations have implied the presence of large-amplitude oscillations. We examine the consequences of these oscillations on the evolution of the cores and the…

Solar and Stellar Astrophysics · Physics 2015-05-19 Avery E. Broderick , Eric Keto

We use our Monte Carlo radiative transfer code to study non-embedded prestellar cores and cores that are embedded at the centre of a molecular cloud. Our study indicates that the temperature inside embedded cores is lower than in isolated…

Astrophysics · Physics 2016-11-03 D. Stamatellos , A. P. Whitworth

Starless molecular cores are natural laboratories for interstellar molecular chemistry research. The chemistry of ices in such objects was investigated with a three-phase (gas, surface, and mantle) model. We considered the center part of…

Astrophysics of Galaxies · Physics 2015-04-24 Juris Kalvans

We investigate molecular evolution in a star-forming core that is initially a hydrostatic starless core and collapses to form a low-mass protostar. The results of a one-dimensional radiation-hydrodynamics calculation are adopted as a…

Astrophysics · Physics 2009-11-13 Yuri Aikawa , Valentine Wakelam , Robin T. Garrod , Eric Herbst

Filamentary structures are ubiquitous in high-mass star-forming molecular clouds. Their relation with high-mass star formation is still to be understood. Here we report interferometric observations toward 8 filamentary high-mass…

Class 0 objects, which are thought to be the youngest protostars, are identified in terms of NIR or radio emission and/or the presence of molecular outflows. We present combined hydrodynamic and radiative transfer simulations of the…

Astrophysics · Physics 2009-11-11 D. Stamatellos , A. P. Whitworth , S. P. Goodwin

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

We present 2D Monte Carlo radiative transfer simulations of prestellar cores. We consider two types of asymmetry: disk-like asymmetry, in which the core is denser towards the equatorial plane than towards the poles; and axial asymmetry, in…

Astrophysics · Physics 2009-11-10 D. Stamatellos , A. P. Whitworth , P. Andre , D. Ward-Thompson

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 complexity of physico-chemical models of star formation is increasing, with models that take into account new processes and more realistic setups. These models allow astrochemists to compute the evolution of chemical species throughout…

Astrophysics of Galaxies · Physics 2019-07-17 Thomas H. G. Vidal , Pierre Gratier , Neil Vaytet , Audrey Coutens , Valentine Wakelam

Models of prestellar cores often assume that the cores are isolated from their environment - material outside the core boundary plays no role in the subsequent evolution. This is unlikely to be the case in reality, where cores are located…

Astrophysics of Galaxies · Physics 2022-12-07 F. D. Priestley , A. P. Whitworth , E. Fogerty

Aims: We investigate from a theoretical perspective if space asteroseismology can be used to distinguish between different thermal structures and shapes of the near-core mixing profiles for different types of coherent oscillation modes in…

Solar and Stellar Astrophysics · Physics 2019-08-20 Mathias Michielsen , May G. Pedersen , Kyle C. Augustson , Stéphane Mathis , Conny Aerts

Interpreting the nature of starless cores has been a prominent goal in star formation for many years. In order to characterise the evolutionary stages of these objects, we perform synthetic observations of a numerical simulation of a…

Solar and Stellar Astrophysics · Physics 2015-06-18 Steve Mairs , Doug Johnstone , Stella S. R. Offner , Scott Schnee

We have made self-consistent models of the density and temperature profiles of the gas and dust surrounding embedded luminous objects using a detailed radiative transfer model together with observations of the spectral energy distribution…

Astrophysics · Physics 2009-11-10 H. Nomura , T. J. Millar

We propose an analytical model for the quasistatic evolution of starless cores confined by a constant external pressure, assuming that cores are isothermal and obey a spherically-symmetric density distribution. We model core evolution for…

Astrophysics of Galaxies · Physics 2016-04-20 Kate Pattle

In this study, we investigate the shapes of starless and protostellar cores using hydrodynamic, self-gravitating adaptive mesh refinement simulations of turbulent molecular clouds. We simulate observations of these cores in dust emission,…

Astrophysics · Physics 2011-02-11 S. S. R. Offner , M. R. Krumholz

The last decade has witnessed significant advances in our observational understanding of the earliest stages of low-mass star formation. The advent of sensitive receivers on large radio telescopes such as the JCMT and IRAM 30m MRT has led…

Astrophysics · Physics 2007-05-23 Philippe Andre , Derek Ward-Thompson , Mary Barsony

Context. he study of prestellar cores is essential to understanding the initial stages of star formation. With $Herschel$ more cold clumps have been detected than ever before. For this study we have selected 21 cold clumps from 20…

Astrophysics of Galaxies · Physics 2015-05-06 A. Parikka , M. Juvela , V. -M. Pelkonen , J. Malinen , J. Harju