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Related papers: Thermal Instability behind a Shock Wave in HI and …

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We use detailed numerical simulations of the coupled chemical, thermal and dynamical evolution of the gas in a turbulent molecular cloud to study the usefulness of the [CI] 609 micron and 370 micron fine structure emission lines as tracers…

Astrophysics of Galaxies · Physics 2015-06-19 Simon C. O. Glover , Paul C. Clark , Milica Micic , Faviola Molina

We present ongoing hydrodynamic and MHD simulations of molecular cloud formation in spiral galaxies. The hydrodynamic results show the formation of molecular gas clouds where spiral shocks compress atomic gas to high densities. The spiral…

Astrophysics · Physics 2007-06-27 Clare Dobbs , Daniel Price , Ian Bonnell

We model a one-dimensional shock-tube using smoothed particle hydrodynamics and investigate the consequences of having finite shock-width in numerical simulations. We investigate the cooling of gas during passage through the shock for…

Astrophysics · Physics 2009-10-31 Roger M. Hutchings , Peter A. Thomas

We study, by means of adaptive mesh refinement hydro- and magnetohydrodynamical simulations that cover a wide range of scales (from kpc to sub-parsec), the dimension of the most dissipative structures and the injection scale of the…

Astrophysics · Physics 2009-11-13 Miguel A. de Avillez , Dieter Breitschwerdt

A recent survey of the fine-structure excitation of neutral carbon reveals that the interstellar medium in the Galactic plane exhibits a thermal pressure, nT/k, that ranges from about 10^3 to 10^4 cm{-3}K from one location to the next, with…

Astrophysics · Physics 2008-11-26 Edward B. Jenkins

Utilizing the Atacama Large Millimeter/submillimeter Array (ALMA), we present CS line maps in five rotational lines ($J_{\rm u}=7, 5, 4, 3, 2$) toward the circumnuclear disk (CND) and streamers of the Galactic Center. Our primary goal is to…

The collision of two plasma clouds at a speed that exceeds the ion acoustic speed can result in the formation of shocks. This phenomenon is observed not only in astrophysical scenarios such as the propagation of supernova remnant (SNR)…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Mark Eric Dieckmann , Gianluca Sarri , Domenico Doria , Hamad Ahmed , Marco Borghesi

Sticky particle calculations indicate that a coherent structure, a dispersion ring, forms when a cloud on a low angular momentum orbit passes close to the dynamical center of an isothermal sphere containing a central point mass. The cloud…

Astrophysics · Physics 2007-05-23 R. H. Sanders

The Draco nebula is a high Galactic latitude interstellar cloud likely to have been formed by the collision of a Galactic halo cloud entering the disk of the Milky Way. Such conditions are ideal to study the formation of cold and dense gas…

Our understanding of how molecular clouds form in the interstellar medium (ISM) would be greatly helped if we had a reliable observational tracer of the gas flows responsible for forming the clouds. Fine structure emission from singly…

Astrophysics of Galaxies · Physics 2019-05-14 Paul C. Clark , Simon C. O. Glover , Sarah E. Ragan , Ana Duarte-Cabral

We use the Gaussian-fit results of Paper I to investigate the properties of interstellar HI in the Solar neighborhood. The Warm and Cold Neutral Media (WNM and CNM) are physically distinct components. The CNM spin temperature histogram…

Astrophysics · Physics 2010-04-06 Carl Heiles , T. H. Troland

We investigate the interplay between the ionization radiation from massive stars and the turbulence inside the surrounding molecular gas thanks to 3D numerical simulations. We used the 3D hydrodynamical code HERACLES to model an initial…

Solar and Stellar Astrophysics · Physics 2015-06-05 P. Tremblin , E. Audit , V. Minier , W. Schmidt , N. Schneider

In the absence of magnetic fields and cosmic rays, radiative cooling laws with a range of dependences on temperature affect the stability of interstellar gas. For about four and a half decades, astrophysicists have recognised the importance…

Astrophysics of Galaxies · Physics 2011-08-08 T. W. Hartquist , A. Y. Wagner , S. A. E. G. Falle , J. M. Pittard , S. Van Loo

The formation of stars occurs in the dense molecular cloud phase of the interstellar medium. Observations and numerical simulations of molecular clouds have shown that supersonic magnetised turbulence plays a key role for the formation of…

Astrophysics of Galaxies · Physics 2016-08-17 Andrew Lehmann , Christoph Federrath , Mark Wardle

This chapter reviews the nature of turbulence in the Galactic interstellar medium (ISM) and its connections to the star formation (SF) process. The ISM is turbulent, magnetized, self-gravitating, and is subject to heating and cooling…

Astrophysics of Galaxies · Physics 2017-03-15 Enrique Vazquez-Semadeni

We investigate thermal regime of the baryons behind shock waves arising in the process of virialization of dark matter halos. We find a fraction of the shocked gas cooled by radiation of HD molecules down to the temperature of the cosmic…

Astrophysics · Physics 2007-05-23 E. O. Vasiliev , Yu. A. Shchekinov

The hot intracluster medium (ICM) is thought to be quiescent with low observed velocity dispersions. Surface brightness fluctuations of the ICM also suggest that its turbulence is subsonic with a Kolmogorov scaling relation, indicating that…

We study the structural evolution of turbulent molecular clouds under the influence of ionizing radiation emitted from a nearby massive star by performing a high resolution parameter study with the iVINE code. The temperature is taken to be…

Solar and Stellar Astrophysics · Physics 2015-05-19 Matthias Gritschneder , Andreas Burkert , Thorsten Naab , Stefanie Walch

Thermal regime of the baryons behind shock waves arising in the process of virialization of dark matter halos is governed at cetrain conditions by radiation of HD lines. A small fraction of the shocked gas can cool down to the temperature…

Astrophysics · Physics 2011-08-31 E. O. Vasiliev , Yu. A. Shchekinov

Wall cooling has substantial effects on the development of instabilities and transition processes in hypersonic boundary layers (HBLs). A sequence of linear stability theory, two-dimensional and non-linear three-dimensional DNSs is used to…

Fluid Dynamics · Physics 2021-04-07 S. Unnikrishnan , Datta V. Gaitonde