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Related papers: Simulations of protostellar collapse using multigr…

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The contraction processes of metal-free molecular clouds of starlike mass (or cloud cores) are investigated. We calculate radiative transfer of the H_2 lines and examine quasi-static contraction with radiative cooling. Comparing two…

Astrophysics · Physics 2009-10-30 Kazuyuki Omukai , Ryoichi Nishi , Hideya Uehara , Hajime Susa

The central region of a circumstellar disk is difficult to resolve in global numerical simulations of collapsing cloud cores, but its effect on the evolution of the entire disk can be significant. We use numerical hydrodynamics simulations…

We investigate protostellar outflow evolution, gas entrainment, and star formation efficiency using radiation-hydrodynamic simulations of isolated, turbulent low-mass cores. We adopt an X-wind launching model, in which the outflow rate is…

Solar and Stellar Astrophysics · Physics 2015-06-18 S. S. R. Offner , H. G. Arce

Thermodynamics play an important role in determining the way a protostellar disc fragments to form planets, brown dwarfs and low-mass stars. We explore the effect that different treatments of radiative transfer have in simulations of…

Astrophysics of Galaxies · Physics 2015-05-13 Dimitris Stamatellos , Anthony Whitworth

Hydrodynamical calculations in three space dimensions of the collapse of an isothermal, centrally condensed, rotating 1 M\sol protostellar cloud are presented. A numerical algorithm involving nested subgrids is used to resolve the region…

Astrophysics · Physics 2007-05-23 Andi Burkert , Peter Bodenheimer

To constrain the nature of the very first stars, we investigate the collapse and fragmentation of primordial, metal-free gas clouds. We explore the physics of primordial star formation by means of three-dimensional simulations of the dark…

Astrophysics · Physics 2009-11-06 Volker Bromm , Paolo S. Coppi , Richard B. Larson

We investigate the role of non-isothermality in gravitational collapse and protostellar accretion by explicitly including the effects of molecular radiative cooling, gas-dust energy transfer, and cosmic ray heating in models of spherical…

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

The activity of massive stars approaching core-collapse can strongly affect the appearance of the star and its subsequent supernova. Late-phase convective nuclear burning generates waves that propagate toward the stellar surface, heating…

High Energy Astrophysical Phenomena · Physics 2023-05-10 Shing-Chi Leung , Jim Fuller

We have computed line emission cooling rates for the main cooling species in models of interstellar molecular clouds. The models are based on numerical simulations of super-sonic magneto-hydrodynamic (MHD) turbulence. Non-LTE radiative…

Astrophysics · Physics 2009-11-06 M. Juvela , P. Padoan , A Nordlund

Accumulating observational evidence for a number of radio galaxies suggests an association between their jets and regions of active star formation. The standard picture is that shocks generated by the jet propagate through an inhomogeneous…

Astrophysics · Physics 2009-11-10 P. Chris Fragile , Stephen D. Murray , Peter Anninos , Wil van Breugel

We discuss recent advances in the radiative-hydrodynamic modeling of core collapse supernovae in multi-dimensions. A number of earlier attempts at fully radiation-hydrodynamic models utilized either the grey approximation to describe the…

Astrophysics · Physics 2017-08-23 F. Douglas Swesty , Eric S. Myra

We present the first $N$-body simulations that adapt the equations of smoothed particle hydrodynamics to capture the effect of dark matter self-interactions which are too frequent to be resolved explicitly. The relevant energy transfer…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-22 Janis Kummer , Marcus Brüggen , Klaus Dolag , Felix Kahlhoefer , Kai Schmidt-Hoberg

The ability of primordial gas to cool in proto-galactic haloes exposed to Lyman-Werner (LW) radiation is critically dependent on the self-shielding of H_2. We perform radiative transfer calculations of LW line photons, post-processing…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jemma Wolcott-Green , Zoltán Haiman , Greg L. Bryan

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

A roughly constant temperature over a wide range of densities is maintained in molecular clouds through radiative heating and cooling. An isothermal equation of state is therefore frequently employed in molecular cloud simulations. However,…

Astrophysics · Physics 2009-11-11 G. Pavlovski , M. D. Smith , M. -M. Mac Low

The stellar initial mass function (IMF) is playing a critical role in the history of our universe. We propose a theory that is based solely on local processes, namely the dust opacity limit, the tidal forces and the properties of the…

Astrophysics of Galaxies · Physics 2019-10-09 Patrick Hennebelle , Yueh-Ning Lee , Gilles Chabrier

Processing by interstellar photons affects the composition of the icy mantles on interstellar grains. The rate of photodissociation in solids differs from that of molecules in the gas phase. The aim of this work was to determine an average,…

Astrophysics of Galaxies · Physics 2018-05-16 Juris Kalvans

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

First hydrostatic cores are predicted by theories of star formation, but their existence has never been demonstrated convincingly by (sub)millimeter observations. Furthermore, the multiplicity at the early phases of the star formation…

Solar and Stellar Astrophysics · Physics 2015-06-11 Benoît Commerçon , François Levrier , Anaëlle J. Maury , Thomas Henning , Ralf Launhardt

We present the results of an investigation of the effects of Far Ultraviolet (FUV) radiation from hot early type OB stars on clumps in star-forming molecular clouds. Clumps in Photodissociation regions (PDRs) undergo external heating which,…

Astrophysics · Physics 2009-11-07 Uma Gorti , David Hollenbach