English
Related papers

Related papers: Non-equilibrium chemistry and cooling in the diffu…

200 papers

We present three-dimensional astrochemical simulations and synthetic observations of magnetised, turbulent, self-gravitating molecular clouds. We explore various galactic interstellar medium environments, including cosmic-ray ionization…

Astrophysics of Galaxies · Physics 2021-01-20 Thomas G. Bisbas , Jonathan C. Tan , Kei E. I. Tanaka

We present a multi-phase representation of the ISM in NB-TSPH simulations of galaxy formation and evolution with particular attention to the case of early-type galaxies. Cold gas clouds are described by the so-called sticky particles…

Astrophysics · Physics 2009-11-13 Emiliano Merlin , Cesare Chiosi

We perform a suite of simulations with realistic gravity and thermal balance in shells to quantify the role of the ratio of cooling time to the free-fall time ($t_{\rm cool}/t_{\rm ff}$) and the amplitude of density perturbations ($\delta…

Astrophysics of Galaxies · Physics 2019-07-17 Prakriti Pal Choudhury , Prateek Sharma , Eliot Quataert

We present a suite of one-dimensional spherically-symmetric hydrodynamic simulations that study the atomic ionization structure of galactic outflows. We track the ionization state of the outflowing gas with a non-equilibrium atomic…

Astrophysics of Galaxies · Physics 2019-05-01 William J Gray , Evan Scannapieco , Matthew D. Lehnert

Star formation depends on the available gaseous "fuel" as well as galactic environment, with higher specific star formation rates where gas is predominantly molecular and where stellar (and dark matter) densities are higher. The partition…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Eve C. Ostriker

The wavelength range 912-2000A (hereafter far-UV) provides access to absorption lines of the interstellar medium (ISM), circumgalactic medium (CGM), and intergalactic medium (IGM) in phases spanning a wide range of ionization, density,…

Astrophysics of Galaxies · Physics 2019-03-19 V. Lebouteiller , D. Kunth , J. Roman-Duval , P. Richter , C. Gry , B. James , A. Aloisi

First we present a recently developed 3D chemodynamical code for galaxy evolution from the K**2 collaboration. It follows the evolution of all components of a galaxy such as dark matter, stars, molecular clouds and diffuse interstellar…

Astrophysics · Physics 2009-11-10 R. Spurzem , P. Berczik , G. Hensler , Ch. Theis , P. Amaro-Seoane , M. Freitag , A. Just

We present an empirical chemical evolution model that explains the distribution of metals in the interstellar medium (ISM) and the circumgalactic medium (CGM) of galaxies based on the UniverseMachine and NeutralUniverseMachine models in the…

Investigating the reliability of the assumption of instantaneous chemical equilibrium (ICE) for calculating the CO number density in the solar atmosphere is of crucial importance for the resolution of the long-standing controversy over the…

Astrophysics · Physics 2009-11-07 A. Asensio Ramos , J. Trujillo Bueno , M. Carlsson , J. Cernicharo

We compare the central mass distribution of galaxies simulated with three different models of the interstellar medium (ISM) with increasing complexity: primordial (H+He) cooling down to 10^4K, additional cooling via metal lines and to lower…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Charlotte Christensen , Fabio Governato , Thomas Quinn , Alyson M. Brooks , David B. Fisher , Sijing Shen , Jacqueline McCleary , James Wadsley

Aims: We systematically explore a plausible subset of the parameter space involving effective temperatures and metallicities of the ionizing stellar sources, the effects of the hardening of their radiation by surrounding leaky HII regions…

Astrophysics of Galaxies · Physics 2019-02-13 J. A. Weber , A. W. A. Pauldrach , T. L. Hoffmann

We present numerical computations and analysis of atomic to molecular (HI-to-H$_2$) transitions in cool ($\sim$100 K) low-metallicity dust-free (primordial) gas, in which molecule formation occurs via cosmic-ray driven negative ion…

Astrophysics of Galaxies · Physics 2021-10-27 Amiel Sternberg , Alon Gurman , Shmuel Bialy

This paper deals with the heating and the ionization of the interstellar medium (ISM) in the 500 central pc of the Milky Way (hereafter Galactic center, GC). We review the results of the Infrared Space Observatory (ISO) observations of a…

Astrophysics · Physics 2017-01-18 N. J. Rodriguez-Fernandez , J. Martin-Pintado

The Intergalactic Medium (IGM) contains $>$50% of the baryonic mass of the Universe, yet the mechanisms responsible for keeping the IGM ionized has not been fully explained. Hence, we investigate ion abundances from the largest blind QSO…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-04 Brad Koplitz , Anjali Ramesh , Sanchayeeta Borthakur

The fate of metals ejected by young OB associations into the Interstellar Medium (ISM) is investigated numerically. In particular, we study the enrichment of the cold gas phase, which is the material that forms molecular clouds. Following…

Astrophysics of Galaxies · Physics 2011-11-09 Evangelia Ntormousi , Andreas Burkert

Isomerism in complex organic molecules provides key insights into the formation mechanisms and physical conditions of the interstellar medium (ISM). Among the C$_2$H$_5$NO isomers, only acetamide and trans-N-methylformamide (trans-NMF) have…

The variation of an ionizing flux as a mechanism to stimulate the condensation of a diffuse gas is considered. To illustrate this effect, two situations are examined: one on the context of pregalactic conditions, and the other on the…

Astrophysics · Physics 2007-05-23 Antonio Parravano , Catherine Pech

Context. The chemistry of the diffuse interstellar medium rests upon three pillars: exothermic ion-neutral reactions (" cold chemistry "), endothermic neutral-neutral reactions with significant activation barriers (" warm chemistry "), and…

The wavelength dependences of interstellar extinction and polarization, supplemented by observed elemental abundances and the spectrum of infrared emission from dust heated by starlight, strongly constrain dust models. One dust model that…

Astrophysics of Galaxies · Physics 2009-03-11 B. T. Draine

We investigate the role of non-isothermality in gravitational collapse and protostellar accretion by explicitly including the effects of molecular radiative cooling, gas-dust energy transfer, and cosmic ray heating in models of spherical…

Astrophysics · Physics 2009-11-13 E. I. Vorobyov , Shantanu Basu