Metal Enrichment of the Primordial Interstellar Medium through Three-dimensional Hydrodynamical Evolution of the First Supernova Remnant

AbstractWe report on a study of interstellar turbulence driven by both correlated and isolated supernova explosions. We use three-dimensional hydrodynamic models of a vertically stratified interstellar medium run with the adaptive mesh refinement code Flash at a maximum resolution of 2 pc, with a grid size of 0.5 × 0.5 × 10 kpc. Cold dense clouds form even in the absence of self-gravity due to the collective action of thermal instability and supersonic turbulence. Studying these clouds, we show that it can be misleading to predict physical properties such as the star formation rate or the stellar initial mass function using numerical simulations that do not include self-gravity of the gas. Even if all the gas in turbulently Jeans unstable regions in our simulation is assumed to collapse and form stars in local freefall times, the resulting total collapse rate is significantly lower than the value consistent with the input supernova rate. The amount of mass available for collapse depends on scale, suggesting a simple translation from the density PDF to the stellar IMF may be questionable. Even though the supernova-driven turbulence does produce compressed clouds, it also opposes global collapse. The net effect of supernova-driven turbulence is to inhibit star formation globally by decreasing the amount of mass unstable to gravitational collapse.

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Heating of the Interstellar Medium by Supernova Remnants

Symposium - International Astronomical Union ◽

10.1017/s0074180900034173 ◽

1983 ◽

Vol 101 ◽

pp. 385-392

Author(s):

Donald P. Cox

Keyword(s):

Interstellar Medium ◽

Supernova Remnants ◽

Supernova Remnant ◽

Low Density ◽

The Sun ◽

X Ray ◽

Interstellar Material ◽

X Ray Background

We observe the heating of interstellar material in young supernova remnants (SNR). In addition, when analyzing the soft X-ray background we find evidence for large isolated regions of apparently hot, low density material. These, we infer, may have been heated by supernovae. One such region seems to surround the Sun. This has been modeled as a supernova remnant viewed from within. The most reasonable parameters are ambient density no ~ 0.004 cm−3, radius of about 100 pc, age just over 105 years (Cox and Anderson 1982).

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G18.95-1.1, A Composite Supernova Remnant Interacting with the Ambient Interstellar Medium

International Astronomical Union Colloquium ◽

10.1017/s0252921100102465 ◽

1988 ◽

Vol 101 ◽

pp. 253-256

Author(s):

E. Fürst ◽

W. Reich ◽

E. Hummel ◽

Y. Sofue

Keyword(s):

Spectral Line ◽

Interstellar Medium ◽

Radio Source ◽

Supernova Remnant ◽

Radio Continuum ◽

New Radio ◽

Galactic Radio

AbstractNew radio continuum and spectral line observations of the Galactic radio source G18.95-1.1 are reported. The distance to G18.95-1.1 is 2 kpc as derived from HI-21 cm spectral line observations. These data also indicate an interaction with the interstellar medium. The radio continuum observations classify G18.95-1.1 as a composite supernova remnant.

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