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Observations of dark cloud cores have been carried out in the mid-infrared using ISOCAM and in the far-infrared using ISOPHOT, both aboard the Infrared Space Observatory. The cores are in most cases detected in emission at 200 and 170…

Astrophysics · Physics 2007-05-23 Aurore Bacmann , Philippe Andre , Derek Ward-Thompson

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 have performed a dense core survey toward the Infrared Dark Cloud G14.225-0.506 at 3 mm continuum emission with the Atacama Large Millimeter/Submillimeter Array (ALMA). This survey covers the two hub-filament systems with an angular…

[abridged] We investigate the velocity structure of protostellar cores that result from non-magnetic numerical models of the gravoturbulent fragmentation of molecular cloud material. A large fraction of the cores analyzed are ``quiescent'',…

Prestellar cores exhibit a strong chemical differentiation, which is mainly caused by the freeze-out of molecules onto the grain surfaces. Understanding this chemical structure is important, because molecular lines are often used as probes…

Astrophysics of Galaxies · Physics 2015-06-17 S. Maret , E. A Bergin , M. Tafalla

Recent high-resolution studies of the L1544 protostellar core by Tafalla et al. and Williams et al. reveal the structure and kinematics of the gas. The observations of this prestellar core provide a natural test for theoretical models of…

Astrophysics · Physics 2009-10-31 Glenn E. Ciolek , Shantanu Basu

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

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

Using recent dust continuum data, we generate the intrinsic ellipticity distribution of dense, starless molecular cloud cores. Under the hypothesis that the cores are all either oblate or prolate randomly-oriented spheroids, we show that a…

Astrophysics · Physics 2009-11-07 Charles L. Curry

L1521E is a dense starless core in Taurus that was found to have relatively low molecular depletion by earlier studies, thus suggesting a recent formation. We aim to characterize the chemical structure of L1521E and compare it to the more…

Astrophysics of Galaxies · Physics 2019-10-09 Z. Nagy , S. Spezzano , P. Caselli , A. Vasyunin , M. Tafalla , L. Bizzocchi , D. Prudenzano , E. Redaelli

Various spectral emission lines from star-forming molecular cloud core L1517B manifest red asymmetric double-peaked profiles with stronger red peaks and weaker blue peaks, in contrast to the oft-observed blue-skewed molecular spectral line…

Solar and Stellar Astrophysics · Physics 2015-05-30 Tian-Ming Fu , Yang Gao , Yu-Qing Lou

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 deuterium fractionation in starless cores gives us a clue to estimate their lifetime scales, thus allowing us to distinguish between different dynamical theories of core formation. Cores also seem to be subject to a differential N2 and…

Astrophysics of Galaxies · Physics 2020-04-08 Sheng-Jun Lin , Laurent Pagani , Shih-Ping Lai , Charlène Lefèvre , François Lique

Studies of the structure and kinematics of cores associated with the regions of massive star and star cluster formation are necessary for constructing scenario for the evolution of these objects. We analyzed spectral maps of the massive…

Astrophysics of Galaxies · Physics 2025-03-13 L. E. Pirogov , P. M. Zemlyanukha , E. M. Dombek

We study the formation, evolution and collapse of dense cores by tracking structures in a magnetohydrodynamic simulation of a star-forming cloud. We identify cores using the dendrogram algorithm and utilize machine learning techniques,…

Understanding the physical properties of star-forming cores as mass reservoirs for protostars, and the impact of turbulence, is crucial in star formation studies. We implemented passive tracer particles in clump-scale numerical simulations…

Astrophysics of Galaxies · Physics 2025-01-08 Shingo Nozaki , Hajime Fukushima , Kazuki Tokuda , Masahiro N. Machida

G10.21-0.31 is a 70 $\mu$m-dark high-mass starless core ($M>300$ $\mathrm{M_{\odot}}$ within $r<0.15$ pc) identified in $Spitzer$, $Herschel$, and APEX continuum surveys, and is believed to harbor the initial stages of high-mass star…

Astrophysics of Galaxies · Physics 2023-03-15 Wenyu Jiao , Ke Wang , Thushara G. S. Pillai , Tapas Baug , Siju Zhang , Fengwei Xu

The Chamaeleon clouds are excellent targets for low-mass star formation studies. Cha I and II are actively forming stars while Cha III shows no sign of ongoing star formation. We aim to determine the driving factors that have led to the…

Astrophysics of Galaxies · Physics 2015-02-18 A. E. Tsitali , A. Belloche , R. T. Garrod , B. Parise , K. M. Menten

Pre-stellar cores represent the initial conditions of star formation. Although these initial conditions in nearby low-mass star-forming regions have been investigated in detail, such initial conditions remain vastly unexplored for massive…

Molecular line observations of starless (prestellar) cores combined with a chemical evolution modeling and radiative transfer calculations are a powerful tool to study the earliest stages of star formation. However, conclusions drawn from…

Astrophysics · Physics 2009-11-13 Ya. Pavlyuchenkov , Th. Henning , D. Wiebe
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