English
Related papers

Related papers: Characterizing the velocity field in hydrodynamica…

200 papers

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

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

In this study, the main goal is to understand the molecular cloud core collapse through the stages of first and second hydrostatic core formation. We investigate the properties of Larson's first and second cores following the evolution of…

Solar and Stellar Astrophysics · Physics 2018-10-24 Asmita Bhandare , Rolf Kuiper , Thomas Henning , Christian Fendt , Gabriel-Dominique Marleau , Anders Kölligan

We study the formation and evolution of several molecules in a collapsing interstellar cloud using a reasonably large reaction network containing more then four hundred atomic and molecular species. We employ a time dependent, spherically…

Astrophysics · Physics 2009-06-30 Ankan Das , Sandip Kumar Chakrabarti , Kinsuk Acharyya , Sonali Chakrabarti

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

Young protostellar discs are likely to be both self-gravitating, and to support grain growth to sizes where the particles decoupled from the gas. This combination could lead to short-wavelength fragmentation of the solid component in…

Earth and Planetary Astrophysics · Physics 2023-05-17 Cristiano Longarini , Philip J. Armitage , Giuseppe Lodato , Daniel J. Price , Simone Ceppi

We present a scenario for the formation of disks which explains not only the properties of normal galaxies, but the properties of the population of low surface brightness galaxies (LSBs) as well. We use a gravitationally self-consistent…

Astrophysics · Physics 2009-10-28 J. J. Dalcanton , D. N. Spergel , F J Summers

We present results from the first three-dimensional radiation hydrodynamical calculations to follow the collapse of a molecular cloud core beyond the formation of the stellar core. We find the energy released by the formation of the stellar…

Solar and Stellar Astrophysics · Physics 2015-05-18 Matthew R. Bate

We present results of hydrodynamic simulations of star formation triggered by cloud-cloud collisions. During the early stages of star formation, low-mass objects form by gravitational instabilities in protostellar discs. A number of these…

Astrophysics · Physics 2008-02-29 Spyridon Kitsionas , Anthony P. Whitworth , Ralf S. Klessen

We report results from twelve simulations of the collapse of a molecular cloud core to form one or more protostars, comprising three field strengths (mass-to-flux ratios, {\mu}, of 5, 10, and 20) and four field geometries (with values of…

Solar and Stellar Astrophysics · Physics 2017-08-28 Benjamin T. Lewis , Matthew R. Bate

Star formation in molecular clouds is clumpy, hierarchically subclustered. Fractal structure also emerges in hydro-dynamical simulations of star-forming clouds. Simulating the formation of realistic star clusters with hydro-dynamical…

The complexity of physico-chemical models of star formation is increasing, with models that take into account new processes and more realistic setups. These models allow astrochemists to compute the evolution of chemical species throughout…

Astrophysics of Galaxies · Physics 2019-07-17 Thomas H. G. Vidal , Pierre Gratier , Neil Vaytet , Audrey Coutens , Valentine Wakelam

(Abridged) Aims & Methods. A two-dimensional, semi-analytical model is presented that follows, for the first time, the chemical evolution from a collapsing molecular cloud (a pre-stellar core) to a protostar and circumstellar disk. The…

Solar and Stellar Astrophysics · Physics 2009-11-13 R. Visser , E. F. van Dishoeck , S. D. Doty , C. P. Dullemond

The classical picture of a star-forming filament is a near-equilibrium structure, with collapse dependent on its gravitational criticality. Recent observations have complicated this picture, revealing filaments as a mess of apparently…

Astrophysics of Galaxies · Physics 2014-02-12 Nickolas Moeckel , Andreas Burkert

A minimum in stellar velocity dispersion is often observed in the central regions of disc galaxies. To investigate the origin of this feature, known as a {\sigma}-drop, we analyse the stellar kinematics of a high-resolution N-body + smooth…

A physical model and two-dimensional numerical method for computing the evolution and spectra of protostellar clouds are described. The physical model is based on a system of magneto-gasdynamical equations, including ohmic and ambipolar…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 A. G. Zhilkin , Ya. N. Pavlyuchenkov , S. N. Zamozdra

We study the structure and evolution of the very early protostellar disk (``protodisk'') just after protostar formation, where disk self-gravity dominates and the stellar contribution is dynamically minor. The disk redistributes angular…

Solar and Stellar Astrophysics · Physics 2026-02-05 Majd Noel , Rahul Khanna , Shahram Abbassi , Sami Dib , Shantanu Basu

The physical conditions in a collapsing cloud can be traced by observations of molecular lines. To correctly interpret these observations the abundance distributions of the observed species need to be derived. The chemistry in a collapsing…

Solar and Stellar Astrophysics · Physics 2009-11-13 R. J. van Weeren , C. Brinch , M. R. Hogerheijde

We investigate the formation of protostellar clusters during the collapse of dense molecular cloud cores with a focus on the evolution of potential and kinetic energy, the degree of substructure, and the early phase of mass segregation. Our…

Solar and Stellar Astrophysics · Physics 2015-06-03 Philipp Girichidis , Christoph Federrath , Richard Allison , Robi Banerjee , Ralf Klessen

Improving our understanding of the initial conditions and earliest stages of star formation is crucial to gain insight into the origin of stellar masses, multiple systems, and protoplanetary disks. We review the properties of low-mass dense…

Astrophysics · Physics 2008-01-29 Philippe André , Shantanu Basu , Shu-ichiro Inutsuka