中文
相关论文

相关论文: A measurement of the turbulence-driven density dis…

200 篇论文

This study is motivated by recent observations on ubiquitous interstellar density filaments and guided by modern theories of compressible magnetohydrodynamic (MHD) turbulence. The interstellar turbulence shapes the observed density…

星系天体物理 · 物理学 2019-08-07 Siyao Xu , Suoqing Ji , A. Lazarian

Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass from the surrounding cloud material. Molecular cloud regions without turbulent driving sources, or where turbulence is driven…

天体物理学 · 物理学 2009-11-06 Ralf Klessen

The propagation of high-energy cosmic rays through giant molecular clouds constitutes a fundamental process in astronomy and astrophysics. The diffusion of cosmic-rays through these magnetically turbulent environments is often studied…

高能天体物理现象 · 物理学 2015-05-20 Marco Fatuzzo , Fulvio Melia , Elizabeth Todd , Fred Adams

Recent advances in understanding of the basic properties of compressible Magnetohydrodynamic (MHD) turbulence call for revisions of some of the generally accepted concepts. First, MHD turbulence is not so messy as it is usually believed. In…

天体物理学 · 物理学 2009-11-10 A. Lazarian , J. Cho

We present the detection analysis of a diffuse molecular cloud at z$_{abs}$=2.4636 towards the quasar SDSS J1513+0352(z$_{em}\,\simeq$ 2.68) observed with the X-shooter spectrograph(VLT). We measure very high column densities of atomic and…

The structure of molecular clouds can be characterized with the probability distribution function (PDF) of the mass surface density. In particular, the properties of the distribution can reveal the nature of the turbulence and star…

星系天体物理 · 物理学 2015-06-22 Rachel L. Ward , James Wadsley , Alison Sills

The density distribution of supersonic isothermal turbulence plays a critical role in many astrophysical systems. It is commonly approximated by a lognormal distribution with a variance of $\sigma_{s,{\rm V}}^2 \approx \ln(1 + b^2 M_{\rm…

星系天体物理 · 物理学 2026-01-15 Evan Scannapieco , Marcus Brüggen , Philipp Grete , Liubin Pan

With a goal toward deriving the physical conditions in external galaxies, we present a survey of the formaldehyde emission in a sample of starburst systems. By extending a technique used to derive the spatial density in star formation…

天体物理学 · 物理学 2009-11-13 Jeffrey G. Mangum , Jeremy Darling , Karl M. Menten , Christian Henkel

Turbulence is a fundamental parameter in models of grain growth during the early stages of planet formation. As such, observational constraints on its magnitude are crucial. Here we self-consistently analyze ALMA CO(2-1), SMA CO(3-2), and…

地球与行星天体物理 · 物理学 2018-04-11 Kevin M. Flaherty , A. Meredith Hughes , Richard Teague , Jacob B. Simon , Sean M. Andrews , David J. Wilner

We present a self-consistent hydrodynamical simulation of a Milky Way-like galaxy, at the resolution of 0.05 pc. The model includes star formation and a new implementation of stellar feedback through photo-ionization, radiative pressure and…

We use numerical simulations to study the effect of nonlinear MHD waves in a stratified, self-gravitating molecular cloud that is bounded by a hot and tenuous external medium. In a previous paper, we had shown the details of a standard…

天体物理学 · 物理学 2009-11-11 Takahiro Kudoh , Shantanu Basu

We present a set of numerical experiments designed to systematically investigate how turbulence and magnetic fields influence the morphology, energetics, and dynamics of filaments produced in wind-cloud interactions. We cover 3D…

星系天体物理 · 物理学 2017-12-06 Wladimir Banda-Barragán , Christoph Federrath , Roland Crocker , Geoffrey Bicknell

The observed rapid onset of star formation in molecular clouds requires rapid formation of dense fragments which can collapse individually before being overtaken by global gravitationally-driven flows. Many previous investigations have…

天体物理学 · 物理学 2009-11-13 F. Heitsch , L. Hartmann , A. Burkert , ;

Super-sonic turbulence fragments molecular clouds (MC) into a very complex density field with density contrasts of several orders of magnitude. A fraction of the gas is locked into dense and gravitationally bound cores, which collapse as…

天体物理学 · 物理学 2007-05-23 Paolo Padoan , AAke Nordlund , Ornolfur Einar Rognvaldsson , Alyssa Goodman

To study the interaction of star-formation and turbulent molecular cloud structuring, we analyse numerical models and observations of self-gravitating clouds using the Delta-variance as statistical measure for structural characteristics. In…

天体物理学 · 物理学 2009-11-07 Volker Ossenkopf , Ralf Klessen , Fabian Heitsch

We explore whether observed molecular clouds could include a substantial population of unbound clouds. Using simulations which include only turbulence and gravity, we are able to match observed relations and naturally reproduce the observed…

星系天体物理 · 物理学 2014-03-05 Rachel L. Ward , James Wadsley , Alison Sills

We investigate observational signatures of triggered star formation in bright rimmed clouds (BRCs) by using molecular line transfer calculations based on radiation-hydrodynamic radiatively-driven-implosion models. We find that for BRCs the…

星系天体物理 · 物理学 2015-06-15 Thomas J. Haworth , Tim J. Harries , David M. Acreman , David A. Rundle

I review recent results derived from numerical simulations of the turbulent interstellar medium (ISM), in particular concerning the nature and formation of turbulent clouds, methods for comparing the structure in simulations and…

天体物理学 · 物理学 2018-03-28 Enrique Vázquez-Semadeni

It appears that the majority of rapidly-, well-localized gamma-ray bursts with undetected, or dark, optical afterglows, or `dark bursts' for short, occur in clouds of size R > 10L_{49}^{1/2} pc and mass M > 3x10^5L_{49} M_{sun}, where L is…

天体物理学 · 物理学 2009-11-07 Daniel E. Reichart , Paul A. Price

It is speculated that the high star-formation efficiency observed in spiral-arm molecular clouds is linked to the prevalence of compressive (curl-free) turbulent modes, while the shear-driven solenoidal (divergence-free) modes appear to be…

星系天体物理 · 物理学 2022-07-20 Raffaele Rani , Toby J. T. Moore , David J. Eden , Andrew J. Rigby