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Related papers: The Origins of Protostellar Core Angular Momenta

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Angular momentum plays a crucial role in the formation of stars and planets. It has long been noticed that parcels of gas in molecular clouds need to reduce their specific angular momentum by 6 to 7 orders of magnitude to participate in the…

Astrophysics of Galaxies · Physics 2015-06-15 Arnaud Belloche

The early evolution of protostellar, star-forming discs, including their density structure, turbulence, magnetic dynamics, and accretion variability, remains poorly understood. We present high-resolution magnetohydrodynamic simulations,…

Solar and Stellar Astrophysics · Physics 2025-08-28 Trey Qingyun Yang , Christoph Federrath

In this study we investigate the formation and properties of prestellar and protostellar cores using hydrodynamic, self-gravitating Adaptive Mesh Refinement simulations, comparing the cases where turbulence is continually driven and where…

Astrophysics · Physics 2009-11-13 S. S. R. Offner , M. R. Krumholz , R. I. Klein , C. F. McKee

Theoretical studies of collapsing clouds have found that even a relatively weak magnetic field (B) may prevent the formation of disks and their fragmentation. However, most previous studies have been limited to cases where B and the…

Solar and Stellar Astrophysics · Physics 2015-06-04 Marc Joos , Patrick Hennebelle , Andrea Ciardi

The connection between dense gas cores and their infant protostars is key to understanding how stars form in molecular clouds. In this paper we investigate the properties, persistence, and protostellar content of cores that would be…

We perform radiation hydrodynamical simulations of protostellar collapse in spherical symmetry, with a special focus on very low-mass objects, i.e. brown dwarfs and sub-brown dwarfs. The inclusion of a realistic equation of state that…

Solar and Stellar Astrophysics · Physics 2019-01-01 Torsten Stamer , Shu-ichiro Inutsuka

It is generally believed that angular momentum is distributed during the gravitational collapse of the primordial star forming cloud. However, so far there has been little understanding of the exact details of the distribution. We use the…

Astrophysics of Galaxies · Physics 2015-12-14 Jayanta Dutta

We present measurements of the mean dense core lifetimes in numerical simulations of magnetically supercritical, turbulent, isothermal molecular clouds, in order to compare with observational determinations. "Prestellar" lifetimes (given as…

We obtain self-similar solutions that describe the gravitational collapse of nonrotating, isothermal, magnetic molecular cloud cores. We use simplifying assumptions but explicitly include the induction equation, and the semianalytic…

Astrophysics · Physics 2009-10-30 Ioannis Contopoulos , Glenn E. Ciolek , Arieh Konigl

The current study was developed to provide a database of relatively simple numerical simulations of protostellar collapse, as a template library for observations of cores and very young protostars, and for researchers who wish to test their…

Solar and Stellar Astrophysics · Physics 2018-08-08 Neil Vaytet , Troels Haugbølle

In star forming regions, we can observe different evolutionary stages of various objects and phenomena such as molecular clouds, protostellar jets and outflows, circumstellar disks, and protostars. However, it is difficult to directly…

Solar and Stellar Astrophysics · Physics 2015-05-19 Masahiro N. Machida

The theory of how low mass stars form from the collapse of a dense molecular cloud core has been well-established for decades. Thanks to significant progress in computing and numerical modelling, more physical models have been developed and…

Solar and Stellar Astrophysics · Physics 2024-01-05 Alison K. Young

Using axisymmetric simulations coupling special relativistic MHD, an approximate post-Newtonian gravitational potential and two-moment neutrino transport, we show different paths for the formation of either protomagnetars or stellar mass…

Solar and Stellar Astrophysics · Physics 2017-05-09 Martin Obergaulinger , Miguel-Ángel Aloy

We develop a statistical approach for description of dense structures (cores) in molecular clouds that might be progenitors of stars. Our basic assumptions are a core mass-density relationship and a power-law density distribution of these…

Solar and Stellar Astrophysics · Physics 2012-06-08 Sava Donkov , Orlin Stanchev , Todor V. Veltchev

We review the properties of low mass dense molecular cloud cores, including starless, prestellar, and Class 0 protostellar cores, as derived from observations. In particular we discuss them in the context of the current debate surrounding…

Astrophysics · Physics 2007-05-23 D. Ward-Thompson , P. Andre , R. Crutcher , D. Johnstone , T. Onishi , C. Wilson

Star formation in our Galaxy occurs in molecular clouds that are self-gravitating, highly turbulent, and magnetized. We study the conditions under which cloud cores inherit large-scale magnetic field morphologies and how the field is…

Astrophysics of Galaxies · Physics 2017-03-29 Philip Mocz , Blakesley Burkhart , Lars Hernquist , Chris McKee , Volker Springel

Stellar core collapse events are expected to produce gravitational waves via several mechanisms, most of which are not yet fully understood due to the current limitations in the numerical simulations of these events. In this paper, we begin…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Kyle Crocker , Tanner Prestegard , Vuk Mandic , Tania Regimbau , Keith Olive , Elisabeth Vangioni

Motivated by recent observational and numerical studies suggesting that collapsing protostellar cores may be replenished from the local environment, we explore the evolution of protostellar cores submerged in the external counter-rotating…

Solar and Stellar Astrophysics · Physics 2016-03-23 Eduard I. Vorobyov , Zsolt Regaly , Manuel Guedel , D. N. C. Lin

We present Atacama Large Millimeter/submillimeter Array observations of the $\sim$10 kAU environment surrounding 21 protostars in the Orion A molecular cloud tracing outflows. Our sample is composed of Class 0 to flat-spectrum protostars,…

We study numerically the evolution of rotating cloud cores, from the collapse of a magnetically supercritical core to the formation of a protostar and the development of a protostellar disk during the main accretion phase. We find that the…

Astrophysics · Physics 2009-11-13 E. I. Vorobyov , Shantanu Basu