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Related papers: Turbulence measurements from HI absorption spectra

200 papers

We present a unified analysis of the O{\sc vi} absorption-lines seen in the disk and halo of the Milky Way, high velocity clouds, the Magellanic Clouds, starburst galaxies, and the intergalactic medium. We show that these disparate systems…

Astrophysics · Physics 2009-11-07 T. M. Heckman , C. A. Norman , D. K. Strickland , K. R. Sembach

Combined HI emission-absorption studies constrain the spin temperature and phase structure of the neutral atomic hydrogen interstellar medium (ISM), but have largely been limited to the Milky Way and the Local Group. We extend this…

We explore what dominant physical mechanism sets the kinetic energy contained in neutral, atomic (HI) gas. We compare the HI line widths predicted from turbulence driven by supernova (SN) explosions and magneto-rotational instability (MRI)…

Astrophysics of Galaxies · Physics 2009-11-13 D. Tamburro , H. -W. Rix , A. K. Leroy , M. -M. Mac Low , F. Walter , R. C. Kennicutt , E. Brinks , W. J. G. de Blok

The statistical properties of interstellar turbulence are studied by means of three-dimensional high-resolution HD and MHD simulations of a SN-driven ISM. It is found that the longitudinal and transverse turbulent length scales have time…

Astrophysics · Physics 2017-08-23 Miguel A. de Avillez , Dieter Breitschwerdt

The paper analyzes the absorption line profile at 21 cm for the hydrogen atom in the interstellar medium. The hydrogen atom is treated as a three-level system illuminated by a powerful light source at neighboring resonances corresponding to…

Atomic Physics · Physics 2018-11-05 D. Solovyev

We present a physically-based absorption-line model for the spectroscopic study of the intergalactic medium (IGM). This model adopts results from Cloudy simulations and theoretical calculations by Gnat and Sternberg (2007) to examine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Yangsen Yao , J. Michael Shull , Charles W. Danforth , Brian A. Keeney , John T. Stocke

We study the dynamics of phase transitions in the interstellar medium by means of three-dimensional hydrodynamic numerical simulations. We use a realistic cooling function and generic nonequilibrium initial conditions to follow the…

Astrophysics · Physics 2009-11-07 Alexei G. Kritsuk , Michael L. Norman

We investigate properties of turbulence and turbulent transport of non-inertial particles described in terms of turbulent thermal diffusion in strongly inhomogeneous and anisotropic convection forced by two similar turbulence generators…

Fluid Dynamics · Physics 2025-12-17 E. Zarbib , E. Elmakies , O. Shildkrot , N. Kleeorin , A. Levy , I. Rogachevskii

Stellar irradiation and particles forcing strongly affect the immediate environment of extrasolar giant planets orbiting near their parent stars. Here, we use far-ultraviolet emission spectra from HD209458 in the wavelength range…

Earth and Planetary Astrophysics · Physics 2014-11-20 Lotfi Ben-Jaffel , Sona Hosseini

We compare observations of HI from the Very Large Array (VLA) and the Arecibo Observatory and observations of HCO$^+$ from the Atacama Large Millimeter/submillimeter Array (ALMA) and the Northern Extended Millimeter Array (NOEMA) in the…

Resolving the phase structure of neutral hydrogen (HI) is crucial for understanding the life cycle of the interstellar medium (ISM). However, accurate measurements of HI temperature and density are limited by the availability of background…

Astrophysics of Galaxies · Physics 2020-08-19 Claire E. Murray , J. E. G. Peek , Chang-Goo Kim

Recent targeted studies of associated HI absorption in radio galaxies are starting to map out the location, and potential cosmological evolution, of the cold gas in the host galaxies of Active Galactic Nuclei (AGN). The observed 21 cm…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 J. R. Allison , E. M. Sadler , S. J. Curran , S. N. Reeves

Turbulence can transport angular momentum in protoplanetary disks and influence the growth and evolution of planets. With spatially and spectrally resolved molecular emission line measurements provided by (sub)millimeter interferometric…

We report the discovery of a threshold in the HI column density of Galactic gas clouds below which the formation of the cold phase of HI is inhibited. This threshold is at $N_{HI} = 2 \times 10^{20}$ per cm$^{2}$; sightlines with lower HI…

Astrophysics of Galaxies · Physics 2013-02-20 Nissim Kanekar , Robert Braun , Nirupam Roy

We submit that non thermalized support for the outer intracluster medium in relaxed galaxy clusters is provided by turbulence, driven by inflows of intergalactic gas across the virial accretion shocks. We expect this component to increase…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 A. Cavaliere , A. Lapi , R. Fusco-Femiano

We use Keck HIRES spectra of three intermediate redshift QSOs to study the physical state and kinematics of the individual components of CIV selected heavy element absorption systems. Fewer than 8 % of all CIV lines with column densities…

Astrophysics · Physics 2009-10-28 M. Rauch , W. L. W. Sargent , D. S. Womble , T. A. Barlow

The gas in the interstellar medium (ISM) of galaxies is supersonically turbulent. Measurements of turbulence typically rely on cold gas emission lines for low-z galaxies and warm ionized gas observations for z>0 galaxies. Studies of warm…

We use observations of the neutral atomic hydrogen (HI) 21-cm emission line to study the spatial distribution of the HI gas in a 80$\degree\times~$90$\degree$ region of the Galaxy halo. The HI column densities in the range of…

Astrophysics of Galaxies · Physics 2017-09-20 Ericson López , Jairo Armijos , Mario Llerena , Franklin Aldás

In this paper we investigate how convective instabilities influence heat conduction in the intracluster medium (ICM) of cool-core galaxy clusters. The ICM is a high-beta, weakly collisional plasma in which the transport of momentum and heat…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Henrik N. Latter , Matthew W. Kunz

We present a survey of O VI line widths obtained from hydrodynamic simulations that model the mixing between High Velocity Clouds and the circumgalactic medium and track the non-equilibrium ionization populations of the ions. We run 10…

Astrophysics of Galaxies · Physics 2025-09-16 Chen Wang , Eric Goetz , Robin Shelton