English
Related papers

Related papers: Bonnor-Ebert sphere collapse in filamentary struct…

200 papers

Simulations of idealised star-forming filaments of finite length typically show core growth which is dominated by two cores forming at its respective end. The end cores form due to a strong increasing acceleration at the filament ends which…

Astrophysics of Galaxies · Physics 2023-01-11 Stefan Heigl , Elena Hoemann , Andreas Burkert

The gravitational collapse of a spherical cloud core is investigated by numerical calculations. The initial conditions of the core lie close to the critical Bonnor-Ebert sphere with a central density of \sim 10^4 cm^{-3} in one model…

Astrophysics · Physics 2009-11-10 Yuri Aikawa , Eric Herbst , Helen Roberts , Paola Caselli

The onset of star formation is set by the collapse of filaments in the interstellar medium. From a theoretical point of view, an isolated cylindrical filament forms cores via the edge effect. Due to the self-gravity of a filament, the…

Astrophysics of Galaxies · Physics 2023-09-08 Elena Hoemann , Stefan Heigl , Andreas Burkert

The structure of protostellar cores can often be approximated by isothermal Bonnor-Ebert spheres (BES) which are stabilized by an external pressure. For the typical pressure of $10^4k_B\,\mathrm{K\,cm^{-3}}$ to…

Astrophysics of Galaxies · Physics 2021-07-07 Oliver Zier , Andreas Burkert , Christian Alig

In order to understand the collapse dynamics of observed low-mass starless cores, we revise the conventional stability condition of hydrostatic Bonnor-Ebert spheres to take internal motions into account. Because observed starless cores…

Astrophysics of Galaxies · Physics 2015-06-15 Young Min Seo , Seung Soo Hong , Yancy L. Shirley

Low-mass stars are generally understood to form by the gravitational collapse of the dense molecular clouds known as starless cores. Continuum observations have not been able to distinguish among the several different hypotheses that…

Solar and Stellar Astrophysics · Physics 2015-06-23 Eric Keto , Paola Caselli , Jonathan Rawlings

We present a detailed study of the collapse of molecular cloud cores using high resolution 3D adaptive mesh refinement (AMR) numerical simulations. In this first in a series of investigations our initial conditions consists of spherical…

Astrophysics · Physics 2009-11-10 Robi Banerjee , Ralph E. Pudritz , Lindsay Holmes

We summarize the current status of the turbulent model of star formation in turbulent molecular clouds. In this model, clouds, clumps and cores form a hierarchy of nested density fluctuations caused by the turbulence, and either collapse or…

Astrophysics · Physics 2007-05-23 Enrique Vazquez-Semadeni

Fragmentation of filaments into dense cores is thought to be an important step in forming stars. The bar-mode instability of spherically collapsing cores found in previous linear analysis invokes a possibility of re-fragmentation of the…

Solar and Stellar Astrophysics · Physics 2017-06-28 Kazuyuki Sugimura , Yurina Mizuno , Tomoaki Matsumoto , Kazuyuki Omukai

(Abridged) We present numerical hydrodynamical simulations of the formation, evolution and gravitational collapse of isothermal molecular cloud cores. A compressive wave is set up in a constant sub-Jeans density distribution of radius r = 1…

We present a solution for the observed core fragmentation of filaments in the Taurus L1517 dark cloud which previously could not be explained (Hacar et. al 2011). Core fragmentation is a vital step for the formation of stars. Observations…

Solar and Stellar Astrophysics · Physics 2017-05-16 Stefan Heigl , Andreas Burkert , Alvaro Hacar

A fundamental issue in star formation is understanding the precise mechanisms leading to the formation of prestellar cores, and their subsequent gravitationally unstable evolution. To address this question, we carefully construct a suite of…

Astrophysics of Galaxies · Physics 2025-05-13 Sanghyuk Moon , Eve C. Ostriker

If the split, asymmetric molecular spectral line profiles that are seen in many starless cores are interpreted as indicative of global collapse or expansion of the core then one possible implication is that most starless cores have short…

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

We investigate prestellar core formation and accretion based on three-dimensional hydrodynamic simulations. Our simulations represent local $\sim 1$pc regions within giant molecular clouds where a supersonic turbulent flow converges,…

Solar and Stellar Astrophysics · Physics 2015-06-10 Munan Gong , Eve C. Ostriker

Observations of prestellar cores in star-forming filaments show two distinct morphologies. While molecular line measurements often show broad cores, submillimeter continuum observations predominantly display pinched cores compared to the…

Astrophysics of Galaxies · Physics 2018-08-15 Stefan Heigl , Matthias Gritschneder , Andreas Burkert

Prestellar cores are generally spheroidal, some of which appear oblate while others appear prolate. Very few of them appear circular in projection. Little, however, is understood about the processes or the physical conditions under which…

Astrophysics of Galaxies · Physics 2022-04-13 S. Anathpindika , J. Di Francesco

Recent observations have revealed the presence of small fibres or sub-filaments within larger filaments. We present a numerical fragmentation study of fibrous filaments investigating the link between cores and sub-filaments using…

Astrophysics of Galaxies · Physics 2020-08-12 S. D. Clarke , G. M. Williams , S. Walch

We investigate the Hierarchical Gravitational Fragmentation scenario through numerical simulations of the prestellar stages of the collapse of a marginally gravitationally unstable isothermal sphere immersed in a strongly gravitationally…

Astrophysics of Galaxies · Physics 2015-10-26 Raúl Naranjo-Romero , Enrique Vázquez-Semadeni , Robert M. Loughnane

We examine the role of the gravitational instability in an isothermal, self-gravitating layer threaded by magnetic fields on the formation of filaments and dense cores. Using numerical simulation we follow the non-linear evolution of a…

Solar and Stellar Astrophysics · Physics 2015-06-19 Sven Van Loo , Eric Keto , Qizhou Zhang

Core collapse is a prominent evolutionary stage of self-gravitating systems. In an idealised collisionless approximation, the region around the cluster core evolves in a self-similar way prior to the core collapse. Thus, its radial density…

Astrophysics of Galaxies · Physics 2018-12-05 Václav Pavlík , Ladislav Šubr
‹ Prev 1 2 3 10 Next ›