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Related papers: Density distributions of outflow driven turbulence

200 papers

Machine learning has demonstrated remarkable promise for solving the trajectory generation problem and in paving the way for online use of trajectory optimization for resource-constrained spacecraft. However, a key shortcoming in current…

Robotics · Computer Science 2025-01-03 Julia Briden , Breanna Johnson , Richard Linares , Abhishek Cauligi

Molecular clouds exhibit lognormal probability density functions (PDF) of mass densities, which are thought to arise as a consequence of isothermal, supersonic turbulence. Star formation is then widely assumed to occur in perturbations in…

Astrophysics of Galaxies · Physics 2018-10-10 Evan Scannapieco , Mohammadtaher Safarzadeh

Supersonic turbulence plays a critical role in shaping astrophysical systems, from molecular clouds to the circumgalactic medium. Key properties of this turbulence include the Mach number, driving scale, and nature of the driving mechanism,…

Astrophysics of Galaxies · Physics 2025-06-02 Philipp Grete , Evan Scannapieco , Marcus Brüggen , Liubin Pan

(abridged) The nature of early Class 0/I protostellar discs is not clearly understood. Early protostellar discs are needed to drive molecular outflows and jets observed in star forming regions, but there has been some debate to how they…

Solar and Stellar Astrophysics · Physics 2012-03-08 Dennis F. Duffin , Ralph E. Pudritz , Daniel Seifried , Robi Banerjee , Ralf S. Klessen

The probabilistic approach to turbulence is applied to investigate density fluctuations in supersonic turbulence. We derive kinetic equations for the probability distribution function (PDF) of the logarithm of the density field, $s$, in…

Astrophysics of Galaxies · Physics 2018-10-24 Liubin Pan , Paolo Padoan , Åke Nordlund

We present numerical simulations of decaying hydrodynamic turbulence initially driven by solenoidal (divergence-free) and compressive (curl-free) driving. Most previous numerical studies for decaying turbulence assume an isothermal equation…

Astrophysics of Galaxies · Physics 2020-11-25 Jeonghoon Lim , Jungyeon Cho

We characterize the physical properties of star-formation driven outflows in a sample of 29 local dwarf galaxies drawn from the Dwarf Galaxy Survey. We make use of Herschel/PACS archival data to search for atomic outflow signatures in the…

(Abridged). We present numerical simulations of isothermal, MHD, supersonic turbulence, designed to test various hypotheses frequently assumed in star formation(SF) theories. We consider three simulations, each with a different combination…

Astrophysics of Galaxies · Physics 2015-06-17 Alejandro González-Samaniego , Enrique Vázquez-Semadeni , Ricardo F. González , Jongsoo Kim

Our work is motivated by the analysis of ash plume dynamics, arising in the study of volcanic eruptions. Such phenomena are characterized by large Reynolds number (exceeding $10^7$) and a large number of polydispersed particles~[1]. Thus,…

Star formation is intimately linked to the dynamical evolution of molecular clouds. Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass via accretion from the surrounding cloud…

Astrophysics · Physics 2007-05-23 Ralf Klessen

We analyse extinction maps of nearby Giant Molecular Clouds to forge a link between driving processes of turbulence and modes of star formation. Our investigation focuses on cloud structure in the column density range above the self…

Astrophysics of Galaxies · Physics 2015-05-28 J. Rowles , D. Froebrich

We analyze the statistics and star formation rate obtained in high-resolution numerical experiments of forced supersonic turbulence, and compare with observations. We concentrate on a systematic comparison of solenoidal (divergence-free)…

Solar and Stellar Astrophysics · Physics 2015-05-14 C. Federrath , J. Duval , R. S. Klessen , W. Schmidt , M. -M. Mac Low

Most stars form in binaries and the evolution of their discs remains poorly understood. To shed light on this subject, we carry out 3D ideal MHD simulations with the AMR code FLASH of binary star formation for separations of…

Earth and Planetary Astrophysics · Physics 2019-05-14 Rajika L. Kuruwita , Christoph Federrath

Molecular clouds have broad linewidths suggesting turbulent supersonic motions in the clouds. These motions are usually invoked to explain why molecular clouds take much longer than a free-fall time to form stars. It has classically been…

Astrophysics · Physics 2011-02-11 Mordecai-Mark Mac Low

Supersonic turbulence occurs in many environments, particularly in astrophysics. In the crucial case of isothermal turbulence, the probability density function (PDF) of the logarithmic density, $s$, is well measured, but a theoretical…

Astrophysics of Galaxies · Physics 2024-10-31 Evan Scannapieco , Liubin Pan , Edward Buie , Marcus Brüggen

The compressibility of molecular cloud (MC) turbulence plays a crucial role in star formation models, because it controls the amplitude and distribution of density fluctuations. The relation between the compressive ratio (the ratio of…

Astrophysics of Galaxies · Physics 2016-07-06 Liubin Pan , Paolo Padoan , Troels Haugbolle , Aake Nordlund

We investigate the evolution of fossil cavities produced by extinct YSO jets and wide angle outflows. Fossil cavities are ellipsoidal or cylindrical shells of swept-up of ambient (molecular cloud) material moving at low velocities. The…

Astrophysics · Physics 2008-11-26 Andrew J. Cunningham , Adam Frank , Alice C. Quillen , Eric G. Blackman

We present three numerical simulations of randomly driven, isothermal, non-magnetic, self-gravitating turbulence with different rms Mach numbers Ms and physical sizes L, but approximately the same value of the virial parameter, alpha approx…

We present results from high-resolution three-dimensional simulations of the turbulent interstellar medium that study the influence of the nature of the turbulence on the formation of molecular hydrogen. We have examined both solenoidal…

Solar and Stellar Astrophysics · Physics 2015-05-27 Milica Micic , Simon C. O. Glover , Christoph Federrath , Ralf S. Klessen

In this study we investigate the formation and properties of prestellar and protostellar cores using hydrodynamic, self-gravitating Adaptive Mesh Refinement simulations, comparing the cases where turbulence is continually driven and where…

Astrophysics · Physics 2009-11-13 S. S. R. Offner , M. R. Krumholz , R. I. Klein , C. F. McKee