The Influence of the Gravitational Acceleration on the Supernova-Driven P arker Instability

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

16 pages, 6 ps figs, corrected references, MNRAS, 325, 208

Scientific paper

10.1046/j.1365-8711.2001.04411.x

Within a framework of 2D MHD simulations, we explore the dynamical regimes initi ated by a supernova explosion in a magnetized stratified ISM. We concentrate on the formation of large scale magnetic structures and outflows connected with the Parker instability. For the sake of simplicity we show only models with a fixed explosion energy corresponding to a single SN occuring in host galaxies with different fixed values of the gravitational acceleration $g$ and different ratios of specific heats. We show that in general depending on these two parameters, three different regimes are possible: a) a slowly growing Parker instability on time scales much longer than the galac tic rotation period for small $g$, b) the Parker instability growing at roughly the rotation period, which for ratios of specific heats larger than 1 is accompanied byan outflow resulting from the explosion for intermediate $g$, and c) a rapidly g rowing instability and a strong blowout flow for large $g$. By means of numerical simul ations and analytical estimates we show that the explosion energy and gravitational acceleration which separate the three regimes scale as $Eg^2\sim $const in the 2D case. We expect that in the 3D case this scaling law is $Eg^3\sim $const. Our simulations demonstrate furthermore, that a single SN explosion can lead to the growth of multiple Parker loops in the disc and large scale magnetic field loops in the halo, extending over 2-3 kpc horizontally and up to 3 kpc vertically abov e the midplane of the disc.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The Influence of the Gravitational Acceleration on the Supernova-Driven P arker Instability does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Influence of the Gravitational Acceleration on the Supernova-Driven P arker Instability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Influence of the Gravitational Acceleration on the Supernova-Driven P arker Instability will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-353674

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.