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Related papers: Molecular Cloud Evolution

200 papers

We compile a holistic scenario for molecular cloud (MC) evolution and control of the star formation efficiency (SFE), and present a first set of numerical tests of it. A {\it lossy} compressible cascade can generate density fluctuations and…

Astrophysics · Physics 2009-11-07 E. Vazquez-Semadeni , J. Ballesteros-Paredes , R. S. Klessen

Molecular-line observations of star-forming cloud cores indicate that they are not the flattened structures traditionally considered by theory. Rather, they are elongated, perhaps in the direction of their internal magnetic field. We are…

Astrophysics · Physics 2009-11-06 Charles L. Curry , Steven W. Stahler

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

The structure of molecular clouds can be characterized with the probability distribution function (PDF) of the mass surface density. In particular, the properties of the distribution can reveal the nature of the turbulence and star…

Astrophysics of Galaxies · Physics 2015-06-22 Rachel L. Ward , James Wadsley , Alison Sills

Filamentary molecular clouds are recognized as primary sites for the formation of stars. Specifically, regions characterized by the overlapping point of multiple filaments, known as hub regions, often associated with active star formation.…

Astrophysics of Galaxies · Physics 2024-08-19 Raiga Kashiwagi , Kazunari Iwasaki , Kohji Tomisaka

Giant molecular clouds (GMCs) are the sites of star formation and stellar feedback in galaxies. Their properties set the initial conditions for star formation and their lifecycles determine how feedback regulates galaxy evolution. In recent…

Astrophysics of Galaxies · Physics 2022-03-21 Mélanie Chevance , Mark R. Krumholz , Anna F. McLeod , Eve C. Ostriker , Erik W. Rosolowsky , Amiel Sternberg

The asymmetry in the cosmic microwave background (CMB) towards several nearby galaxies detected by Planck data is probably due to the rotation of "cold gas" clouds present in the galactic halos. In 1995 it had been proposed that galactic…

Astrophysics of Galaxies · Physics 2021-09-27 Noraiz Tahir , Asghar Qadir , Muhammad Sakhi , Francesco De Paolis

Most formation scenarios of globular clusters assume a molecular cloud as the progenitor of the stellar system. However, it is still unclear, how this cloud is transformed into a star cluster, i.e. how the destructive processes related to…

Astrophysics · Physics 2009-11-07 Christian Theis

Observations of both star-forming regions and young, gas-free stellar associations indicate that most nearby molecular clouds form stars only over a short time span before dispersal; large-scale flows in the diffuse interstellar medium have…

Astrophysics · Physics 2008-11-26 Lee Hartmann , Javier Ballesteros-Paredes , Edwin A. Bergin

Molecular clouds, the birthplaces of stars in galaxies, form dynamically from the diffuse atomic gas of the interstellar medium (ISM). The ISM is also threaded by magnetic fields which have a large impact on its dynamics. In particular,…

Astrophysics of Galaxies · Physics 2015-09-14 Robi Banerjee , Bastian Körtgen

Star clusters are known to be formed in turbulent molecular clouds. How turbulence is driven in molecular clouds and what effect this has on star formation is still unclear. We compare a simulation setup with turbulent driving everywhere in…

Astrophysics of Galaxies · Physics 2022-09-28 Jamie D. Smith , James E. Dale , Sarah E. Jaffa , Martin G. H. Krause

The colliding flows (CF) model is a well-supported mechanism for generating molecular clouds. However, to-date most CF simulations have focused on the formation of clouds in the normal-shock layer between head-on colliding flows. We…

Astrophysics of Galaxies · Physics 2016-05-31 Erica Fogerty , Adam Frank , Fabian Heitsch , Jonathan Carroll-Nellenback , Christina Haig , Marissa Adams

The most recent observational evidence seems to indicate that giant molecular clouds are predominantly gravitationally unbound objects. In this paper we show that this is a natural consequence of a scenario in which cloud-cloud collisions…

Astrophysics of Galaxies · Physics 2015-05-27 C. L. Dobbs , A. Burkert , J. E. Pringle

Turbulence is thought to be a primary driving force behind the early stages of star formation. In this framework large, self gravitating, turbulent clouds fragment into smaller clouds which in turn fragment into even smaller ones. At the…

Solar and Stellar Astrophysics · Physics 2016-03-17 David Guszejnov , Philip F. Hopkins

Recent observations suggest galaxies may ubiquitously host a molecular component to their multiphase circumgalactic medium (CGM). However, the structure and kinematics of the molecular CGM remains understudied theoretically and largely…

Astrophysics of Galaxies · Physics 2023-08-16 Ryan Jeffrey Farber , Max Gronke

We investigate star formation at very early evolutionary phases in five massive clouds in the inner 500 pc of the Galaxy, the Central Molecular Zone. Using interferometer observations of H$_2$O masers and ultra-compact H II regions, we find…

In the standard scenario of isolated low-mass star formation, strongly magnetized molecular clouds are envisioned to condense gradually into cores, driven by ambipolar diffusion. Once the cores become magnetically supercritical, they…

Astrophysics · Physics 2007-05-23 Fumitaka Nakamura , Zhi-Yun Li

Stars generally form faster than the ambipolar diffusion time, suggesting that several processes short circuit the delay and promote a rapid collapse. These processes are considered here, including turbulence compression in the outer parts…

Astrophysics · Physics 2009-11-13 Bruce G. Elmegreen

Young massive clusters (YMCs) are recently formed astronomical objects with unusually high star formation rates. We propose the collision of giant molecular clouds (GMCs) as a likely formation mechanism of YMCs, consistent with the YMC…

Astrophysics of Galaxies · Physics 2020-09-30 K. Y. Liow , C. L. Dobbs

We have investigated the possibility of molecular cloud formation via the Collision-induced Magnetic Reconnection (CMR) mechanism of the cold neutral medium (CNM). Two atomic gas clouds with conditions typical of the CNM were set to collide…

Astrophysics of Galaxies · Physics 2024-08-27 Shuo Kong , Rowan J. Smith , David Whitworth , Erika T. Hamden
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