The evolution of flows of stellar mass loss in active galaxies

MacDonald, J.; Bailey, Mark

doi:10.1093/mnras/197.4.995

Cited by 89 publications

(65 citation statements)

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“…Note that the cooling curve ÃðTÞ in principle does not linearly scale; however, we also tested the cooling curve of Sutherland & Dopita (1993) with primordial gas composition. It agrees with the linearly scaled ÃðTÞ by MacDonald & Bailey (1981) within a factor of a few in the temperature range between 10 5 and 10 7 K, which are the shock-heated temperatures of the shells expected in our simulations with v sh % 100 km s À1 . We also find that the cooling of shells ÃðTÞn 2 is not so sensitive to ÃðTÞ but primarily to the density of the shells, n.…”

Section: Shell Formation and Galactic Outflowssupporting

confidence: 87%

“…Our numerical methods and initial conditions generally follow MF99 (see their x 4): we use axisymmetric ratioed grids; a cooling curve by MacDonald & Bailey (1981), linearly scaled by a factor of 10 to account for low metallicity in dwarf galaxies; and a tracer field (Yabe & Xiao 1993) to avoid overcooling in the bubble interiors. Note that the cooling curve ÃðTÞ in principle does not linearly scale; however, we also tested the cooling curve of Sutherland & Dopita (1993) with primordial gas composition.…”

Section: Shell Formation and Galactic Outflowsmentioning

confidence: 99%

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The Influence of Supershells and Galactic Outflows on the Escape of Ionizing Radiation from Dwarf Starburst Galaxies

Fujita

Martin

Low

et al. 2003

ApJ

114

145

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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 M d ¼ 10 8 10 10 M , with exponential surface density profiles as a function of redshift, and model the effects of repeated supernova explosions driving supershells out of the disks, using the hydrodynamic simulation code ZEUS-3D. The amount of star formation is assumed proportional to mass above some density threshold. We vary the threshold to explore the range of star formation efficiencies, f Ã ¼ 0:006, 0.06, and 0.6. We find that the interstellar gas swept up in dense supershells can effectively trap the ionizing photons before the supershells blow out of the disks. The blowouts then create galactic outflows, chimneys that allow the photons to escape directly to the intergalactic medium. Our results are consistent with escape fractions of less than 0.1 measured in local dwarf starburst galaxies, because they are likely observed while the starbursts are young, before blowout. We suggest that high-redshift dwarf starburst galaxies may make a substantial contribution to the UV background radiation with total escape fractions e0.2, as expected if star formation efficiencies are e0:06.

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Section: Shell Formation and Galactic Outflowssupporting

confidence: 87%

Section: Shell Formation and Galactic Outflowsmentioning

confidence: 99%

The Influence of Supershells and Galactic Outflows on the Escape of Ionizing Radiation from Dwarf Starburst Galaxies

Fujita

Martin

Low

et al. 2003

ApJ

114

145

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“…The real composition of each of these species is not of importance since no feedback effects from the species back into the hydrodynamic calculations are taken into account. Radiative cooling is included using the cooling curve from MacDonald & Bailey (1981), which is valid for a gas of approximately solar composition, but is applied to all the gas in the simulations. Applying this cooling curve to the gas consisting of CSM material is reasonable since it has a composition comparable to the solar composition.…”

Section: Methodsmentioning

confidence: 99%

The hydrodynamics of the supernova remnant Cassiopeia A

Veelen

Langer

Vink

et al. 2009

A&A

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Aims. There are large differences in the proposed progenitor models for the Cas A SNR. One of these differences is the presence or absence of a Wolf-Rayet (WR) phase of the progenitor star. The mass loss history of the progenitor star strongly affects the shape of the Supernova remnant (SNR). In this paper we investigate whether the progenitor star of Cas A had a WR phase or not and how long it may have lasted.Methods. We performed two-dimensional multi-species hydrodynamical simulations of the CSM around the progenitor star for several WR life times, each followed by the interaction of the supernova ejecta with the CSM. We then looked at the influence of the length of the WR phase and compared the results of the simulations with the observations of Cas A. Results. The difference in the structure of the CSM, for models with different WR life times, has a strong impact on the resulting SNR. With an increasing WR life time the reverse shock velocity of the SNR decreases and the range of observed velocities in the shocked material increases. Furthermore, if a WR phase occurs, the remainders of the WR shell will be visible in the resulting SNR. Conclusions. Comparing our results with the observations suggests that the progenitor star of Cas A did not have a WR phase. We also find that the quasi-stationary flocculi (QSF) in Cas A are not consistent with the clumps from a WR shell that have been shocked and accelerated by the interaction with the SN ejecta. We can also conclude that for a SN explosion taking place in a CSM that is shaped by the wind during a short (≤ 15000 yr) WR phase, the clumps from the WR shell will be visible inside the SNR.

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“…We ran tests with their cooling curve (MacDonald & Bailey 1981) and with a cooling curve for collisional ionization equilibrium medium (see details in section 2.4 of Paper I). We find no notable differences, mostly because they are similar in the high temperature regime (T 10 5 K) that is relevant for the supernova-wind interaction (Fig.…”

Section: Comparison With Previous Workmentioning

confidence: 99%

Asymmetric supernova remnants generated by Galactic, massive runaway stars

Meyer¹,

Langer²,

Mackey³

et al. 2015

Monthly Notices of the Royal Astronomical Society

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After the death of a runaway massive star, its supernova shock wave interacts with the bow shocks produced by its defunct progenitor, and may lose energy, momentum, and its spherical symmetry before expanding into the local interstellar medium (ISM). We investigate whether the initial mass and space velocity of these progenitors can be associated with asymmetric supernova remnants. We run hydrodynamical models of supernovae exploding in the pre-shaped medium of moving Galactic core-collapse progenitors. We find that bow shocks that accumulate more than about 1.5 M ⊙ generate asymmetric remnants. The shock wave first collides with these bow shocks 160 − 750 yr after the supernova, and the collision lasts until 830 − 4900 yr. The shock wave is then located 1.35 − 5 pc from the center of the explosion, and it expands freely into the ISM, whereas in the opposite direction it is channelled into the region of undisturbed wind material. This applies to an initially 20 M ⊙ progenitor moving with velocity 20 km s −1 and to our initially 40 M ⊙ progenitor. These remnants generate mixing of ISM gas, stellar wind and supernova ejecta that is particularly important upstream from the center of the explosion. Their lightcurves are dominated by emission from optically-thin cooling and by X-ray emission of the shocked ISM gas. We find that these remnants are likely to be observed in the [OIII] λ 5007 spectral line emission or in the soft energy-band of X-rays. Finally, we discuss our results in the context of observed Galactic supernova remnants such as 3C391 and the Cygnus Loop.

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The evolution of flows of stellar mass loss in active galaxies

Cited by 89 publications

References 0 publications

The Influence of Supershells and Galactic Outflows on the Escape of Ionizing Radiation from Dwarf Starburst Galaxies

The Influence of Supershells and Galactic Outflows on the Escape of Ionizing Radiation from Dwarf Starburst Galaxies

The hydrodynamics of the supernova remnant Cassiopeia A

Asymmetric supernova remnants generated by Galactic, massive runaway stars

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