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Related papers: Metal-Absorption Column Densities in Fast Radiativ…

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I present computations of the integrated column densities produced in the post-shock cooling layers and in the radiative precursors of partially-cooled fast shocks as a function of the shock age. The results are applicable to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Orly Gnat

We present new computations of the equilibrium and non-equilibrium cooling efficiencies and ionization states for low-density radiatively cooling gas containing cosmic abundances of the elements H, He, C, N, O, Ne, Mg, Si, S, and Fe. We…

Astrophysics · Physics 2009-11-11 Orly Gnat , Amiel Sternberg

We present computations of the ionization structure and metal-absorption properties of thermally conductive interface layers that surround evaporating warm spherical clouds, embedded in a hot medium. We rely on the analytical formalism of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Orly Gnat , Amiel Sternberg , Christopher F. McKee

We have investigated the ionisation structure of the post-shock regions of magnetic cataclysmic variables using an analytic density and temperature structure model in which effects due to bremsstrahlung and cyclotron cooling are considered.…

Astrophysics · Physics 2009-11-06 Kinwah Wu , Mark Cropper , Gavin Ramsay

Radiative shocks, behind which gas cools faster than the dynamical time, play a key role in many astrophysical transients, including classical novae and young supernovae interacting with circumstellar material. The dense layer behind high…

High Energy Astrophysical Phenomena · Physics 2018-07-04 Elad Steinberg , Brian D. Metzger

In this paper we treat the pre-ionisation problem in shocks over the velocity range $10 < v_{\rm s} < 1500$\,km/s in a self-consistent manner. We identify four distinct classes of solution controlled by the value of the shock precursor…

Instrumentation and Methods for Astrophysics · Physics 2017-04-19 Ralph S. Sutherland , Michael A. Dopita

In an earlier paper we treated the pre-ionisation problem in shocks over the velocity range $20 < v_{\rm s} < 1000$km/s in a fully self-consistent manner. Here we investigate in detail the effect of the upstream UV photon field generated in…

Astrophysics of Galaxies · Physics 2017-04-19 Michael A. Dopita , Ralph S. Sutherland

Cosmic-ray and X-ray ionisations in molecular gas produce a weak far-ultraviolet flux through the radiative decay of H2 molecules that have been excited by collisions with energetic electrons (the Prasad-Tarafdar mechanism). I consider the…

Astrophysics · Physics 2009-10-31 Mark Wardle

Shocks, modelled over a broad range of parameters, are used to construct a new tool to deduce the mechanical energy and physical conditions from observed atomic or molecular emission lines. We compute magnetised, molecular shock models with…

Astrophysics of Galaxies · Physics 2022-03-14 Andrew Lehmann , Benjamin Godard , Gillaume Pineau des Forêts , Alba Vidal-García , Edith Falgarone

We present a new library of fully-radiative shock models calculated with the MAPPINGS III shock and photoionization code. The library consists of grids of models with shock velocities in the range v=100-1000 km/s and magnetic parameters…

Nonequilibrium (time-dependent) cooling rates and ionization state calculations are presented for low-density gas enriched with heavy elements (metals) and photoionized by external ultraviolet/X-ray radiation. We consider a wide range of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Evgenii O. Vasiliev

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

We considered the structure of steady-state radiative shock waves propagating in the partially ionized hydrogen gas with density rho1 = 1e-10 gm/cm^3 and temperature 3000K <= T1 <= 8000K. The radiative shock wave models with electron…

Astrophysics · Physics 2009-11-07 Yu. A. Fadeyev , H. Le Coroller , D. Gillet

The grid of the models of radiative shock waves propagating through partially ionized hydrogen gas with temperature 3000K <= T_1 <= 8000K and density 10^{-12} gm/cm^3 <= \rho_1 <= 10^{-9}gm/cm^3 is computed for shock velocities 20 km/s <=…

Astrophysics · Physics 2009-11-06 Yu. A. Fadeyev , D. Gillet

This paper provides a general reference for deriving the ionizations and metal abundances for absorption-line clouds in photoionization equilibrium with a QSO spectrum. The results include a quantitative assessment of the theoretical…

Astrophysics · Physics 2009-10-30 Fred Hamann

Weakly magnetized shock waves are paramount to a large diversity of environments, including supernova remnants, blazars, and binary-neutron-star mergers. Understanding the distribution of energy between electrons and ions within these…

High Energy Astrophysical Phenomena · Physics 2024-10-22 Arno Vanthieghem , Vasileios Tsiolis , Frederico Fiuza , Kazuhiro Sekiguchi , Anatoly Spitkovsky , Yasushi Todo

The analysis of Balmer-dominated optical spectra from non-radiative (adiabatic) SNRs has shown that the ratio of the electron to proton temperature temperature at the blast wave is close to unity at v_s <= 400 km/s, but declines sharply…

Astrophysics · Physics 2009-11-11 Parviz Ghavamian , J. Martin Laming , Cara E. Rakowski

We have chosen a reduced set of 18 ionization rate equations (for ions of H, C, N, O, S and Ne), which allow us to obtain a moderately accurate estimate of the non-equilibrium radiative cooling function. We evaluate the accuracy of this…

Astrophysics · Physics 2009-10-28 A. Raga , G. Mellema , P. Lundqvist

We present deep spectroscopic (3600 - 24700 A) X-shooter observations of the bright Herbig-Haro object HH1, one of the best laboratories to study the chemical and physical modifications caused by protostellar shocks on the natal cloud. We…

Solar and Stellar Astrophysics · Physics 2015-10-26 T. Giannini , S. Antoniucci , B. Nisini , F. Bacciotti , L. Podio

We study the column densities of neutral atomic, molecular, and warm ionized Galactic gas through their continuous absorption of extragalactic X-ray spectra at |b| > 25 degrees. For N(H,21cm) < 5x10^20 cm^-2 there is an extremely tight…

Astrophysics · Physics 2014-10-13 John S. Arabadjis , Joel N. Bregman
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