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

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The C$^{+}$ ion is an important coolant of interstellar gas, and so the [CII] fine structure line is frequently observed in the interstellar medium. However, the physical and chemical properties of the [CII]-emitting gas are still unclear.…

In this paper, the nonlinear evolution of a bistable interstellar medium is investigated using two-dimensional simulations with a realistic cooling rate, thermal conduction, and physical viscosity. The calculations are performed using…

Astrophysics of Galaxies · Physics 2015-06-17 Kazunari Iwasaki , Shu-ichiro Inutsuka

We perform the first measurement of the thermal and ionization state of the intergalactic medium (IGM) across 0.9 < z < 1.5 using 301 \lya absorption lines fitted from 12 HST STIS quasar spectra, with a total pathlength of \Delta z=2.1. We…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-06 Teng Hu , Vikram Khaire , Joseph F. Hennawi , Todd M. Tripp , Jose Oñorbe , Michael Walther , Zarija Lukic

Galaxy formation and evolution critically depend on understanding the complex photo-chemical processes that govern the evolution and thermodynamics of the InterStellar Medium (ISM). Computationally, solving chemistry is among the most heavy…

Astrophysics of Galaxies · Physics 2024-02-21 Lorenzo Branca , Andrea Pallottini

In the interstellar medium (ISM), the formation of complex organic molecules (COMs) is largely facilitated by surface reactions. However, in cold dark clouds, thermal desorption of COMs is inefficient because of the lack of thermal energy…

Astrophysics of Galaxies · Physics 2022-09-07 Alec Paulive , Joshua T. Carder , Eric Herbst

We characterise the thermal state of the intergalactic medium (IGM) in ten redshift bins in the redshift range $2 \leq z \leq 4$ with a sample of 103 high resolution, high S/N Ly$\alpha$ forest spectra using four different flux distribution…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-20 Prakash Gaikwad , Raghunathan Srianand , Martin G. Haehnelt , Tirthankar Roy Choudhury

A basic model for the formation of non-equilibrium rotational energy distributions is described for reactive, homo-polar diatomic molecules and ions in the interstellar medium. Kinetic models were constructed to calculate the rotational…

Astrophysics of Galaxies · Physics 2015-06-12 Robert J. Glinski , Erik P. Hoy , Clark R. Downum

A roughly constant temperature over a wide range of densities is maintained in molecular clouds through radiative heating and cooling. An isothermal equation of state is therefore frequently employed in molecular cloud simulations. However,…

Astrophysics · Physics 2009-11-11 G. Pavlovski , M. D. Smith , M. -M. Mac Low

The interstellar medium (ISM) of galaxies very often contains a gas component that reaches the temperature of several million degrees, whose physical and chemical properties can be investigated through imaging and spectroscopy in the…

Astrophysics of Galaxies · Physics 2023-04-05 Emanuele Nardini , Dong-Woo Kim , Silvia Pellegrini

An accurate estimate of the interstellar gas density distribution is crucial to understanding the interstellar medium (ISM) and Galactic cosmic rays (CRs). To comprehend the ISM and CRs in a local environment, a study of the diffuse…

High Energy Astrophysical Phenomena · Physics 2020-02-26 T. Mizuno , S. Abdollahi , Y. Fukui , K. Hayashi , T. Koyama , A. Okumura , H. Tajima , H. Yamamoto

We present a generic mechanism for the thermal damping of compressive waves in the interstellar medium (ISM), occurring due to radiative cooling. We solve for the dispersion relation of magnetosonic waves in a two-fluid (ion-neutral) system…

Astrophysics of Galaxies · Physics 2021-11-24 Kedron Silsbee , Alexei V. Ivlev , Munan Gong

The Galaxy is in continuous elemental evolution. Since new elements produced by dying stars are delivered to the interstellar medium, the formation of new enerations of stars and planetary systems is influenced by this metal enrichment. We…

Astrophysics of Galaxies · Physics 2019-08-17 Em. M. Penteado , H. M. Cuppen , H. J Rocha-Pinto

We explore the impact of diffusive cosmic rays (CRs) on the evolution of the interstellar medium (ISM) under varying assumptions of supernova explosion environment. In practice, we systematically vary the relative fractions of supernovae…

Astrophysics of Galaxies · Physics 2022-12-28 Christine M. Simpson , Rüdiger Pakmor , Christoph Pfrommer , Simon C. O. Glover , Rowan Smith

We have carried out the first spatially-resolved investigation of the multi-phase interstellar medium (ISM) at high redshift, using the z=4.24 strongly-lensed sub-millimetre galaxy H-ATLASJ142413.9+022303 (ID141). We present high-resolution…

High quality archival spectra of interstellar absorption from C I toward 9 stars, taken with the Goddard High Resolution Spectrograph on the Hubble Space Telescope, were analyzed. Our sample was supplemented by two sight lines, 23 Ori and…

Astrophysics · Physics 2009-11-07 J. Zsargo , S. R. Federman

Water (H2O) ice is an important solid constituent of many astrophysical environments. To comprehend the role of such ices in the chemistry and evolution of dense molecular clouds and comets, it is necessary to understand the freeze-out,…

Chemistry plays an important role in the interstellar medium (ISM), regulating heating and cooling of the gas, and determining abundances of molecular species that trace gas properties in observations. Although solving the time-dependent…

Astrophysics of Galaxies · Physics 2019-04-05 Munan Gong , Eve C. Ostriker , Mark G. Wolfire

We summarise observations and our current understanding of the interstellar medium (ISM) in galaxies, which mainly consists of three phases: cold atomic or molecular gas and clouds, warm neutral or ionised gas, and hot ionised gas. These…

High Energy Astrophysical Phenomena · Physics 2024-09-02 Manami Sasaki , Gabriele Ponti , Jonathan Mackey

The chemistry of H2O, CO and other small molecular species in an isolated pre-stellar core, L1544, has been assessed in the context of a comprehensive gas-grain chemical model, coupled to an empirically constrained physical/dynamical model.…

Solar and Stellar Astrophysics · Physics 2024-04-25 Jonathan Rawlings , Eric Keto , Paola Caselli

To understand the chemistry of sulphur (S) in the interstellar medium, models need to be tested by observations of S-bearing molecules in different physical conditions. We analyse observations obtained with the IRAM 30m telescope towards 15…

Astrophysics of Galaxies · Physics 2023-10-17 F. Fontani , E. Roueff , L. Colzi , P. Caselli