English
Related papers

Related papers: Turbulent Cooling Flows in Molecular Clouds

200 papers

We present the results from three dimensional hydrodynamical simulations of decaying high-speed turbulence in dense molecular clouds. We compare our results, which include a detailed cooling function, molecular hydrogen chemistry and a…

Astrophysics · Physics 2009-11-07 Georgi Pavlovski , Michael D. Smith , Mordecai-Mark Mac Low , Alexander Rosen

A flux of cosmic rays (CRs) propagating through a diffuse ionized gas can excite MHD waves, thus generating magnetic disturbances. We propose a generic model of CR penetration into molecular clouds through their diffuse envelopes, and…

High Energy Astrophysical Phenomena · Physics 2018-03-14 A. V. Ivlev , V. A. Dogiel , D. O. Chernyshov , P. Caselli , C. -M. Ko , K. S. Cheng

The observational record of turbulence within the molecular gas phase of the interstellar medium is summarized. We briefly review the analysis methods used to recover the velocity structure function from spectroscopic imaging and the…

Astrophysics · Physics 2009-11-11 M. H. Heyer , C. Brunt

A systematic study of the linear thermal instability of a self-gravitating magnetic molecular cloud is carried out for the case when the unperturbed background is subject to local expansion or contraction. We consider the ambipolar…

Astrophysics · Physics 2009-11-11 Mohsen Nejad-Asghar , Jamshid Ghanbari

Stars form in cold dense cores showing subsonic velocity dispersions. The parental molecular clouds display higher temperatures and supersonic velocity dispersions. The transition from core to cloud has been observed in velocity dispersion,…

The gas in galaxy clusters is heated by shock compression through accretion (outer shocks) and mergers (inner shocks). These processes additionally produce turbulence. To analyse the relation between the thermal and turbulent energies of…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-06 Wolfram Schmidt , Jan F. Engels , Jens C. Niemeyer , Ann S. Almgren

The properties of supersonic isothermal turbulence influence a variety of astrophysical phenomena, including the structure and evolution of star forming clouds. This work presents a simple model for the structure of dense regions in…

Astrophysics of Galaxies · Physics 2018-02-28 Brant Robertson , Peter Goldreich

We investigate the core mass distribution (CMD) resulting from numerical models of turbulent fragmentation of molecular clouds. In particular we study its dependence on the sonic root-mean-square Mach number $\Ms$. We analyze simulations…

We argue that bulk spiral flows are ubiquitous in the cool cores (CCs) of clusters and groups of galaxies. Such flows are gauged by spiral features in the thermal and chemical properties of the intracluster medium, by the multi-phase…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Uri Keshet

The transport of magnetic flux to outside of collapsing molecular clouds is a required step to allow the formation of stars. Although ambipolar diffusion is often regarded as a key mechanism for that, it has been recently argued that it may…

Solar and Stellar Astrophysics · Physics 2015-05-27 E. M. de Gouveia Dal Pino , R. Santos-Lima , A. Lazarian , M. R. M. Leão , D. Falceta-Gonçalves , G. Kowal

Protostellar outflows crisscross the regions of star cluster formation, stirring turbulence and altering the evolution of the forming cluster. We model the stirring of turbulent motions by protostellar outflows, building on an observation…

Astrophysics · Physics 2011-02-11 Christopher D. Matzner

We present an investigation on effect of the ion-neutral (or ambipolar) diffusion heating rate on thermal phases of a molecular cloud. We use the modeling of ambipolar diffusion with two-fluid smoothed particle hydrodynamics, as discussed…

Astrophysics · Physics 2008-04-29 M. Nejad-Asghar , D. Molteni

We discuss the role of turbulence in cloud and star formation, as observed in numerical simulations of the interstellar medium. Turbulent compression at the interfaces of colliding gas streams is responsible for the formation of…

Astrophysics · Physics 2007-05-23 E. Vazquez-Semadeni , T. Passot , A. Pouquet

We calculate the evolution of molecular line profiles of HCO$^+$ and C$^{18}$O toward a dense core thatis forming inside a magnetized turbulent molecular cloud. Features of the profiles can be affected more significantly by coupled velocity…

Astrophysics of Galaxies · Physics 2009-07-22 Jeong-Eun Lee , Jongsoo Kim

In many clusters of galaxies there is evidence for cooling flow in the central regions. A possibility is that a fraction of the gas forms cold molecular clouds. We investigate the minimum temperature which can be reached by clouds in…

Astrophysics · Physics 2007-05-23 L. Grenacher , Ph. Jetzer , D. Puy

Galaxy cluster cores are pervaded by hot gas which radiates at far too high a rate to maintain any semblance of a steady state; this is referred to as the cooling flow problem. Of the many heating mechanisms that have been proposed to…

High Energy Astrophysical Phenomena · Physics 2018-05-02 Ellen G. Zweibel , Vladimir V. Mirnov , Mateusz Ruszkowski , Christopher S. Reynolds , H. -Y. Karen Yang , Andrew C. Fabian

Turbulent radiation flow is commonplace in systems with strong, incoherent, light-matter interactions. In astrophysical contexts, photon bubble turbulence is considered a key mechanism behind enhanced radiation transport, and its importance…

Atomic Physics · Physics 2021-07-06 R. Giampaoli , João D. Rodrigues , José A. Rodrigues , José T. Mendonça

The fragmentation of gas to form stars in molecular clouds is intrinsically linked to the turbulence within them. These internal motions are set at the birth of the cloud and may vary with galactic environment and as the cloud evolves. In…

Astrophysics of Galaxies · Physics 2024-07-29 Jiten Dhandha , Zoe Faes , Rowan J. Smith

Cool, dense material is frequently observed to permeate the hot, tenuous solar corona in the form of prominences, spicules and coronal rain. Both the cool material and surrounding corona exist at temperatures that are effectively thermally…

Solar and Stellar Astrophysics · Physics 2026-01-30 B. Snow , A. Hillier

Cool cluster cores are in global thermal equilibrium but are locally thermally unstable. We study a nonlinear phenomenological model for the evolution of density perturbations in the ICM due to local thermal instability and gravity. We have…

Astrophysics of Galaxies · Physics 2015-06-22 Ashmeet Singh , Prateek Sharma