English
Related papers

Related papers: Non-equilibrium Ionization States Within Galactic …

200 papers

We present hydrodynamic simulations of high-velocity clouds (HVCs) traveling through the hot, tenuous medium in the Galactic halo. A suite of models was created using the FLASH hydrodynamics code, sampling various cloud sizes, densities,…

Astrophysics of Galaxies · Physics 2015-05-28 Kyujin Kwak , David B. Henley , Robin L. Shelton

Recent observations have successfully detected UV or infrared flux from galaxies at the epoch of reionization. However, the origin of their radiative properties has not been fully understood yet. Combining cosmological hydrodynamic…

Astrophysics of Galaxies · Physics 2020-06-10 Shohei Arata , Hidenobu Yajima , Kentaro Nagamine , Yuexing Li , Sadegh Khochfar

We investigate models for the photoionization of the widespread diffuse ionized gas in galaxies. In particular we address the long standing question of the penetration of Lyman continuum photons from sources close to the galactic midplane…

Outflows have been shown to be prevalent in galaxies hosting luminous active galactic nuclei (AGNs) and present a physically plausible way to couple the AGN energy output with the interstellar medium of their hosts. Despite their…

Astrophysics of Galaxies · Physics 2016-12-21 Marios Karouzos , Jong-Hak Woo , Hyun-Jin Bae

The Magellanic Stream and several high velocity clouds have now been detected in optical line emission. The observed emission measures and kinematics are most plausibly explained by photoionization due to hot, young stars in the Galactic…

Astrophysics · Physics 2009-10-31 J. Bland-Hawthorn , P. R. Maloney

I explore the thermal evolution and ionization states in gas cooling from an initially hot state in the presence of external photoionizing radiation. I compute the equilibrium and nonequilibrium cooling efficiencies, heating rates, and ion…

Astrophysics of Galaxies · Physics 2017-07-05 Orly Gnat

A population of early star-forming galaxies is the leading candidate for the re-ionization of the universe. It is still unclear what conditions and physical processes would enable a significant fraction of the ionizing photons to escape…

Astrophysics of Galaxies · Physics 2015-09-16 Rachael Alexandroff , Timothy Heckman , Sanchayeeta Borthakur , Roderik Overzier , Claus Leitherer

We present hydrodynamical simulations of galactic winds from star-forming galaxies including non-equilibrium ionization and frequency-dependent radiative transfer, processes that have remained largely unaccounted for in galactic wind…

Astrophysics of Galaxies · Physics 2022-11-30 Kartick C. Sarkar , Amiel Sternberg , Orly Gnat

An accurate treatment of the multiphase interstellar medium (ISM) in hydrodynamic galaxy simulations requires that we follow not only the thermal evolution of the gas, but also the evolution of its chemical state, including its molecular…

Astrophysics of Galaxies · Physics 2015-06-18 Alexander J. Richings , Joop Schaye , Benjamin D. Oppenheimer

We present a new methodology for the analysis of the emission lines of the interstellar medium in the Narrow Line Regions around type-2 Active Galactic Nuclei. Our aim is to provide a recipe that can be used for large samples of objects in…

Astrophysics of Galaxies · Physics 2019-09-25 E. Pérez-Montero , O. L. Dors , J. M. Vílchez , R. García-Benito , M. V. Cardaci , G. F. Hägele

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

Recent suggestions of a "photon underproduction crisis" (Kollmeier \etal\ 2014) have generated concern over the intensity and spectrum of ionizing photons in the metagalactic ultraviolet background (UVB). The balance of hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-23 J. Michael Shull , Joshua Moloney , Charles W. Danforth , Evan M. Tilton

We present cosmological, radiation-hydrodynamics simulations of galaxy formation during the epoch of reionization in an effort towards modelling the interstellar medium (ISM) and interpreting ALMA observations. Simulations with and without…

Astrophysics of Galaxies · Physics 2018-05-02 Harley Katz , Taysun Kimm , Debora Sijacki , Martin Haehnelt

We present a study of the ionized gas in a sample of 65 nearby early-type galaxies, for which we have acquired optical intermediate-resolution spectra. Emission lines are detected in ~89 % of the sample. The incidence of emission appears…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-23 F. Annibali , A. Bressan , R. Rampazzo , W. W. Zeilinger

Using numerical techniques we studied the global stability of cooling flows in giant elliptical galaxies. As an initial equilibrium state we choose the hydrostatic gas recycling model (Kritsuk 1996). Non-equilibrium radiative cooling,…

Astrophysics · Physics 2009-10-30 A. Kritsuk , H. Boehringer , E. Mueller

The galactic gaseous halo is a gas reservoir for the interstellar medium in the galaxy disk, supplying materials for star formation. We developed a gaseous halo model connecting the galaxy disk and the gaseous halo by assuming the star…

Astrophysics of Galaxies · Physics 2018-04-04 Zhijie Qu , Joel N. Bregman

The detections of atomic hydrogen, heavy atoms and ions surrounding the extrasolar giant planet (EGP) HD209458b constrain the composition, temperature and density profiles in its upper atmosphere. Thus the observations provide guidance for…

Earth and Planetary Astrophysics · Physics 2015-06-11 T. T. Koskinen , M. J. Harris , R. V. Yelle , P. Lavvas

We present a simple model that explains the origin of warm diffuse gas seen primarily as highly ionized absorption line systems in the spectra of background sources. We predict the observed column densities of several highly ionized…

Astrophysics of Galaxies · Physics 2017-11-01 Rongmon Bordoloi , Alexander Y. Wagner , Timothy M. Heckman , Colin A. Norman

The processes allowing the escape of ionizing photons from galaxies into the intergalactic medium are poorly known. To understand how Lyman continuum (LyC) photons escape galaxies, we constrain the HI covering fractions and column densities…

Astrophysics of Galaxies · Physics 2018-08-08 Simon Gazagnes , John Chisholm , Daniel Schaerer , Anne Verhamme , Jane R. Rigby , Matthew Bayliss

AGN-driven outflows are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super massive black holes and their host galaxies. This work aims to detect the…