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Related papers: Star formation in expanding shells

200 papers

Using 2D nonlinear simulations, we study the generation and nonlinear evolution of spiral structure in a star-forming multi-component gravitating disk. We confirm in agreement with previous studies the destabilizing role of a cold gaseous…

Astrophysics · Physics 2007-05-23 Vladimir Korchagin , Christian Theis

Dense pockets of cold, molecular gas precede the formation of stars. During their infancy and later phases of evolution, stars inject considerable energy into the interstellar medium by driving shocks either due to ionising radiation or…

Astrophysics of Galaxies · Physics 2011-12-02 S. Anathpindika

We use a high-resolution grid-based hydrodynamics method to simulate the multi-phase interstellar medium in a Milky Way-size quiescent disk galaxy. The models are global and three-dimensional, and include a treatment of star formation and…

Astrophysics · Physics 2009-11-13 Elizabeth J. Tasker , Greg L. Bryan

Most stars form in dense star clusters deeply embedded in residual gas. These objects must therefore be seen as the fundamental building blocks of galaxies. With this contribution some physical processes that act in the very early and also…

Astrophysics · Physics 2009-11-13 Pavel Kroupa

Modelling global disc galaxies is a difficult task which has previously resulted in the small scale physics of the interstellar medium being greatly simplified. In this talk, I compare simulations of galaxies with different ISM properties…

Astrophysics · Physics 2007-11-05 Elizabeth J. Tasker , Greg L. Bryan

The empirical laws of star formation suggest that galactic-scale gravity is involved, but they do not identify the actual triggering mechanisms for clusters in the final stages. Many other triggering processes satisfy the empirical laws…

Astrophysics · Physics 2009-11-07 Bruce G. Elmegreen

We derive an analytic prediction for the star formation rate in environments ranging from normal galactic disks to starbursts and ULIRGs in terms of the observables of those systems. Our calculation is based on three premises: (1) star…

Astrophysics · Physics 2010-04-06 Mark R. Krumholz , Christopher F. McKee

Magnetic fields are important at every scale in the star formation process: from the dynamics of the ISM in galaxies, to the collapse of turbulent molecular clouds to form stars and in the fragmentation of individual star forming cores. The…

Astrophysics · Physics 2008-04-30 Daniel J. Price , Matthew R. Bate , Clare L. Dobbs

Star formation is enhanced in spiral arms because of a combination of orbit crowding, cloud collisions, and gravitational instabilities. The characteristic mass for the instability is 10^7 Msun in gas and 10^5 Msun in stars, and the…

Astrophysics · Physics 2015-05-13 Bruce G. Elmegreen

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

The isothermal gravitational collapse and fragmentation of a region within a molecular cloud and the subsequent formation of a protostellar cluster is investigated numerically. The clump mass spectrum which forms during the fragmentation…

Astrophysics · Physics 2009-10-30 Ralf S. Klessen , Andreas Burkert , Matthew R. Bate

During the last two decades, the focus of star formation research has shifted from understanding the collapse of a single dense core into a star to studying the formation hundreds to thousands of stars in molecular clouds. In this chapter,…

Astrophysics · Physics 2008-01-04 S. T. Megeath , Zhi-Yun Li , Aake Nordlund

We discuss the stability of galactic disks in which the energy of interstellar clouds is gained in encounters with expanding supernova remnants and lost in inelastic collisions. Energy gain and loss processes introduce a phase difference…

Astrophysics · Physics 2009-11-10 Adi Nusser

Understanding the formation of binary and multiple stellar systems largely comes down to studying the circumstances for the fragmentation of a condensing core during the first stages of the collapse. However, the probability of…

Solar and Stellar Astrophysics · Physics 2015-02-11 Evangelia Ntormousi , Patrick Hennebelle

In order to constrain the initial mass function (IMF) of the first generation of stars (Population III), we investigate the fragmentation properties of metal-free gas in the context of a hierarchical model of structure formation. We…

Astrophysics · Physics 2009-10-31 Volker Bromm , Paolo S. Coppi , Richard B. Larson

Young stars form on a wide range of scales, producing aggregates and clusters with various degrees of gravitational self-binding. The loose aggregates have a hierarchical structure in both space and time that resembles interstellar…

Astrophysics · Physics 2007-05-23 B. G. Elmegreen , Y. N. Efremov , R. E. Pudritz , H. Zinnecker

The radial profiles of gas, stars, and far ultraviolet radiation in 20 dwarf Irregular galaxies are converted to stability parameters and scale heights for a test of the importance of two-dimensional (2D) instabilities in promoting star…

Astrophysics of Galaxies · Physics 2015-06-03 Bruce G. Elmegreen , Deidre A. Hunter

Supersonic turbulence fragments the interstellar medium into dense sheets, filaments, cores and large low density voids. The turbulence is driven on large scales, probably predominantly by supernovae. The scaling properties of supersonic…

Astrophysics · Physics 2007-05-23 Aake Nordlund , Paolo Padoan

We invoke star formation triggered by cloud-cloud collisions to explain global star formation rates of disk galaxies and circumnuclear starbursts. Previous theories based on the growth rate of gravitational perturbations ignore the…

Astrophysics · Physics 2009-10-31 Jonathan C. Tan

We briefly review the recent numerical works that have been performed to understand the formation of massive stars. After a brief description of the classical works, we review more specifically $i)$ the problem of building stars more…

Astrophysics of Galaxies · Physics 2012-09-11 Patrick Hennebelle , Benoit Commercon