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Related papers: How Starless Are Starless Cores?

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In a previous paper we identified cores within infrared dark clouds (IRDCs). We regarded those without embedded sources as the least evolved, and labelled them starless. Here we identify the most isolated starless cores and model them using…

We present Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 3 observations of 73 starless and protostellar cores in the Orion B North molecular cloud. We detect a total of 34 continuum sources at 106 GHz, and after comparisons with…

Astrophysics of Galaxies · Physics 2026-05-05 Samuel Fielder , Helen Kirk , Michael Dunham , Stella Offner

A fundamental difference between "core-fed" and "clump-fed" star formation theories lies in the existence or absence of high-mass cores at the prestellar stage. However, only a handful of such cores have been observed. Here, different than…

Astrophysics of Galaxies · Physics 2024-08-12 Wenyu Jiao , Ke Wang , Fengwei Xu

Formation, evolution, and dispersal processes of protoplanetary disks are investigated and the disk lifetime is estimated. Gravitational collapse of a pre-stellar core forms both a central star and a protoplanetary disk. The central star…

Solar and Stellar Astrophysics · Physics 2016-11-22 Shigeo S. Kimura , Masanobu Kunitomo , Sanemichi Z. Takahashi

We recently proposed that molecular cloud dense cores undergo a prolonged period of quasi-static contraction prior to true collapse. This theory could explain the observation that many starless cores exhibit, through their spectral line…

Solar and Stellar Astrophysics · Physics 2015-05-19 Steven W. Stahler , Jeffrey J. Yen

N2H+ observations of molecular cloud cores in Taurus with the Nobeyama 45 m radio telescope are reported. We compare ``cores with young stars'' with ``cores without young stars''. The differences in core radius, linewidth, and core mass are…

Astrophysics · Physics 2009-11-10 K. Tatematsu , T. Umemoto , R. Kandori , Y. Sekimoto

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 distribution of protostar masses is studied for core-environment systems whose duration of infall follows a waiting-time distribution. Each core-environment system has a continuous density profile with no barrier to mass flow. The core…

Astrophysics of Galaxies · Physics 2014-11-20 Philip C. Myers

We perform a virial analysis of starless dense cores in three nearby star-forming regions : L1688 in Ophiuchus, NGC 1333 in Perseus, and B18 in Taurus. Our analysis takes advantage of comprehensive kinematic information for the dense gas in…

We use the COMPLETE Survey's observations of the Perseus star-forming region to assess and intercompare three methods for measuring column density in molecular clouds: extinction mapping (NIR); thermal emission mapping (FIR); and mapping…

Astrophysics · Physics 2011-02-11 Alyssa A. Goodman , Jaime E. Pineda , Scott L. Schnee

Chamaeleon I is the most active region in terms of star formation in the Chamaeleon molecular cloud complex. Its population of prestellar and protostellar cores is not known and a controversy exists concerning its history of star formation.…

Astrophysics of Galaxies · Physics 2011-01-05 A. Belloche , F. Schuller , B. Parise , Ph. André , J. Hatchell , J. K. Jørgensen , S. Bontemps , A. Weiß , K. M. Menten , D. Muders

We discuss problems with some observational estimates indicating long protostellar core lifetimes and large stellar age spreads in molecular clouds. We also point out some additional observational constraints which suggest that protostellar…

Astrophysics · Physics 2007-05-23 Javier Ballesteros-Paredes , Lee Hartmann

The absence of Type IIP core-collapse supernovae arising from progenitors above 17 solar masses suggests the existence of another evolutionary path by which massive stars end their lives. The direct collapse of a stellar core to a black…

Solar and Stellar Astrophysics · Physics 2023-02-16 Robert Byrne , Morgan Fraser

We present a census of molecular outflows across four active regions of star formation in the Perseus molecular cloud (NGC 1333, IC348/HH211, L1448 and L1455), totalling an area of over 1000 sq arcmin. This is one of the largest surveys of…

Astrophysics of Galaxies · Physics 2015-05-19 Emily I. Curtis , John S. Richer , Jonathan J. Swift , Jonathan P. Williams

Class 0 sources are objects representing the earliest phase of the protostellar evolution. Since they are highly obscured by an extended dusty envelope, these objects emit mainly in the far-infrared to millimetre wavelength range. The…

Astrophysics · Physics 2007-05-23 M. Rengel , D. Froebrich , S. Wolf , J. Eisloeffel

We utilize the extensive datasets available for the Perseus molecular cloud to analyze the relationship between the kinematics of small-scale dense cores and the larger structures in which they are embedded. The kinematic measures presented…

Astrophysics of Galaxies · Physics 2015-05-19 Helen Kirk , Jaime E. Pineda , Doug Johnstone , Alyssa Goodman

We present a population study of Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 6 observations of the 100 most gravitationally unstable dense cores in Aquila using a simple mass versus size analysis. We identify 66 continuum…

Astrophysics of Galaxies · Physics 2026-05-05 Samuel Fielder , Helen Kirk , Michael Dunham , Stella Offner

In a previous paper, we modeled the oscillations of a thermally-supported (Bonnor-Ebert) sphere as non-radial, linear perturbations following a standard analysis developed for stellar pulsations. The predicted column density variations and…

Astrophysics · Physics 2009-11-13 Avery E. Broderick , Eric Keto , Charles J. Lada , Ramesh Narayan

Infrared images of the dark cloud core B59 were obtained with the Spitzer Space Telescope as part of the "Cores to Disks" Legacy Science project. Photometry from 3.6-70 microns indicates at least 20 candidate low-mass young stars near the…

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,…