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Aims. The goal of the paper is to present a detailed study of the propagation of low velocity (5 to 25 km s-1) stationary molecular shocks in environments illuminated by an external ultraviolet (UV) radiation field. In particular, we intend…

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

Models of steady-state plane-parallel shock waves propagating through the unperturbed hydrogen gas of temperature T=6000K and density rho = 1e-10 gm/cm^3 are computed for upstream velocities from 15 km/s to 70 km/s. The shock wave structure…

Astrophysics · Physics 2007-05-23 Yu. A. Fadeyev , D. Gillet

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

Context. Atomic and molecular line emissions from shocks may provide valuable information on the injection of mechanical energy in the interstellar medium (ISM), the generation of turbulence, and the processes of phase transition between…

Astrophysics of Galaxies · Physics 2024-08-21 Benjamin Godard , Guillaume Pineau Des Forêts , Shmuel Bialy

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

Aims: Ultraviolet (UV) lines of neutral carbon observed in absorption in the local diffuse interstellar medium (ISM) have long revealed that a substantial fraction of the mass of the gas lies at a thermal pressure one to three orders of…

Astrophysics of Galaxies · Physics 2024-09-04 Benjamin Godard , Guillaume Pineau Des Forêts , Jeremy La Porte , Mona Merlin-Weck

Shocks in astrophysical transients are key sites of particle acceleration. If the shock upstream is optically thick, radiation smoothens the velocity discontinuity at the shock (radiation-mediated shocks). However, in mildly magnetized…

High Energy Astrophysical Phenomena · Physics 2026-05-12 Shunke Ai , Irene Tamborra

The structure of steady plane-parallel radiative shock waves propagating through the hydrogen gas undergoing partial ionization and excitation of bound atomic states is investigated in terms of the self-consistent solution of the equations…

Astrophysics · Physics 2007-05-23 Yu. A. Fadeyev , D. Gillet

Supernovae from core-collapse of massive stars drive shocks into the molecular clouds from which the stars formed. Such shocks affect future star formation from the molecular clouds, and the fast-moving, dense gas with compressed magnetic…

Astrophysics of Galaxies · Physics 2019-11-06 William T. Reach , Le Ngoc Tram , Matthew Richter , Antoine Gusdorf , Curtis DeWitt

The dynamical impact of Lyman-alpha (Ly{\alpha}) radiation pressure on galaxy formation depends on the rate and duration of momentum transfer between Ly{\alpha} photons and neutral hydrogen gas. Although photon trapping has the potential to…

Astrophysics of Galaxies · Physics 2016-12-07 Aaron Smith , Volker Bromm , Abraham Loeb

Modeling subphotospheric shocks in a gamma-ray burst (GRB) is challenging due to the various timescales that must be resolved, and the fact that the same radiation dynamically mediates the shocks while forming the observed signal. Here, we…

High Energy Astrophysical Phenomena · Physics 2026-04-10 Jona Nordin Nobuoka , Filip Alamaa , Felix Ryde , Christoffer Lundman

We study the escape of Lyman continuum radiation from the disks of dwarf starburst galaxies, with and without supershells, by solving the radiation transfer problem of stellar radiation through them. We model disks with Md=10^8-10Msun, with…

Astrophysics · Physics 2009-11-07 Akimi Fujita , Crystal Martin , Mordecai-Mark Mac Low , Tom Abel

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

Supernova shocks into dense molecular cores in IC 443 (clumps B, C, and G) and 3C 391 were observed using the Stratospheric Observatory for Infrared Astronomy and complemented by archival data from the Herschel Space Observatory. The pure…

Astrophysics of Galaxies · Physics 2024-11-07 William T. Reach , Ngoc Le Tram , Curtis DeWitt , Pierre Lesaffre , Benjamin Godard , Antoine Gusdorf

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

We explore the impact of Fermi-like acceleration of Lyman-alpha (Ly{\alpha}) photons across shock fronts on the observed Ly{\alpha} spectral line shape. We first confirm the result of Neufeld & McKee (1988) that this mechanism gives rise to…

Astrophysics of Galaxies · Physics 2015-11-18 Andrew S. Chung , Mark Dijkstra , Benedetta Ciardi , Max Gronke

Sub-photospheric shock dissipation is one of the main proposed mechanisms for producing the prompt gamma-ray burst (GRB) emission. Such shocks are mediated by scattering of radiation. We introduce a time dependent, special relativistic code…

High Energy Astrophysical Phenomena · Physics 2018-05-02 Christoffer Lundman , Andrei Beloborodov , Indrek Vurm

The Galactic interstellar medium abounds in low-velocity shocks with velocities less than, say, about 70 km/s. Some are descendants of higher velocity shocks, while others start off at low velocity (e.g., stellar bow shocks, intermediate…

Astrophysics of Galaxies · Physics 2023-02-28 S. R. Kulkarni , J. Michael Shull

Stars are bad neighbors: they often disturb their surroundings. They sometimes travel very fast through the interstellar medium (ISM). They frequently undergo violent ejection events which leave an imprint on their neighborhood (jets,…

Solar and Stellar Astrophysics · Physics 2018-08-07 L. N. Tram , P. Lesaffre , S. Cabrit , P. T. Nhung
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