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Related papers: A ram-pressure threshold for star formation

200 papers

We present a simple model for the number distribution of maximally star-forming clumps in rotating disk galaxies, at high-$z$ with high gas surface densities. By combining assumptions surrounding marginal stability of disks against…

Astrophysics of Galaxies · Physics 2024-11-01 Matthew E. Orr , Douglas Rennehan

Sticking properties rule the early phases of pebble growth in protoplanetary discs in which grains regularly travel from cold, water-rich regions to the warm inner part. This drift affects composition, grain size, morphology, and water…

Earth and Planetary Astrophysics · Physics 2020-07-03 T. Bogdan , C. Pillich , J. Landers , H. Wende , G. Wurm

We present radiation-magneto-hydrodynamic simulations of star formation in self-gravitating, turbulent molecular clouds, modeling the formation of individual massive stars, including their UV radiation feedback. The set of simulations have…

Astrophysics of Galaxies · Physics 2019-09-30 Chong-Chong He , Massimo Ricotti , Sam Geen

Supermassive stars (SMSs) with mass $\sim10^{5}~\rm{M}_{\odot}$ are promising candidates for the origin of supermassive black holes observed at redshift $\gtrsim6$. They are supposed to form as a result of rapid accretion of primordial gas,…

Astrophysics of Galaxies · Physics 2019-01-09 Ryoki Matsukoba , Sanemichi Z. Takahashi , Kazuyuki Sugimura , Kazuyuki Omukai

We present a detailed parameter study of collapsing turbulent cloud cores, varying the initial density profile and the initial turbulent velocity field. We systematically investigate the influence of different initial conditions on the star…

Solar and Stellar Astrophysics · Physics 2015-05-19 Philipp Girichidis , Christoph Federrath , Robi Banerjee , Ralf S. Klessen

We use a suite of 3D simulations of star-forming molecular clouds, with and without stellar feedback, magnetic fields, and driven turbulence, to study the compression and expansion rates of the gas as functions of density. We show that,…

Star formation in galaxies is triggered by a combination of processes, including gravitational instabilities, spiral wave shocks, stellar compression, and turbulence compression. Some of these persist in the far outer regions where the…

Astrophysics · Physics 2009-11-13 Bruce G. Elmegreen , Deidre A. Hunter

At the earliest evolutionary stages, massive star-forming regions are deeply embedded within their natal cores and not observable at optical and near-infrared wavelengths. Interferometric high-spatial resolution mm dust continuum…

Astrophysics · Physics 2015-11-11 Henrik Beuther

Galaxies undergoing ram-pressure stripping develop gaseous tails that can extend several kiloparsecs outside the galaxy disc. We used far-ultraviolet and H$\alpha$ imaging from the GASP survey to investigate how different stages of…

The main accretion phase of star formation is investigated in clouds with different metallicities in the range of 0 \le Z \le Z_\odot, resolving the protostellar radius. Starting from a near-equilibrium prestellar cloud, we calculate the…

Solar and Stellar Astrophysics · Physics 2015-06-23 Masahiro N. Machida , Teppei Nakamura

We present a mechanism for the crystalline silicate production associated with the formation and subsequent destruction of massive fragments in young protostellar disks. The fragments form in the embedded phase of star formation via disk…

Solar and Stellar Astrophysics · Physics 2015-05-27 Eduard I. Vorobyov

We construct strangelets, taking into account electrostatic effects, including Debye screening, and arbitrary surface tension sigma of the interface between vacuum and quark matter. We find that there is a critical surface tension…

High Energy Physics - Phenomenology · Physics 2009-11-11 Mark G. Alford , Krishna Rajagopal , Sanjay Reddy , Andrew Steiner

To make predictions for the existence of ``dark galaxies'', it is necessary to understand what determines whether a gas cloud will form stars. Star formation thresholds are generally explained in terms of the Toomre criterion for…

Astrophysics · Physics 2009-11-13 Joop Schaye

Empirical star formation laws from the last 20 years are reviewed with a comparison to simulations. The current form in main galaxy disks has a linear relationship between the star formation rate per unit area and the molecular cloud mass…

Astrophysics of Galaxies · Physics 2015-05-27 Bruce G. Elmegreen

We present the physical and evolutionary properties of prestellar and protostellar clumps in the Herschel Infrared GALactic plane survey (Hi-GAL) in two large areas centered in the Galactic plane and covering the tips of the long Galactic…

Accretion disks that become gravitationally unstable can fragment into stellar or sub-stellar companions. The formation and survival of these fragments depends on the precarious balance between self-gravity, internal pressure, tidal…

Solar and Stellar Astrophysics · Physics 2015-05-28 Kaitlin M. Kratter , Ruth A. Murray-Clay

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

In this paper we investigate the level of star formation activity within nearby molecular clouds. We employ a uniform set of infrared extinction maps to provide accurate assessments of cloud mass and structure and compare these with…

Astrophysics of Galaxies · Physics 2015-05-19 Charles J. Lada , Marco Lombardi , João F. Alves

We use 3035 Herschel-SPIRE 500$\mu$m sources from 20.3 sq deg of sky in the HerMES Lockman, ES1 and XMM-LSS areas to estimate the star-formation rate density at z = 1-6. 500 mu sources are associated first with 350 and 250 mu sources, and…

The role played by velocity fields in the fragmentation of a cold medium and in the formation of protostars is studied. The velocity field is modeled with a compressible turbulent flow. A supersonic turbulent velocity field can fragment the…

Astrophysics · Physics 2015-06-24 Paolo Padoan