Global simulations of galactic dynamo driven by cosmic-rays and exploding magnetized stars
Abstract
We conduct global galactic--scale magnetohydrodynamical (MHD) simulations of the cosmic--ray driven dynamo. We assume that exploding stars deposit small--scale, randomly oriented, dipolar magnetic fields into the differentially rotating ISM, together with a portion of cosmic rays, accelerated in supernova shocks. Our simulations are performed with the aid of a new parallel MHD code PIERNIK. We demonstrate that dipolar magnetic fields supplied on small SN--remnant scales, can be amplified exponentially by the CR--driven dynamo to the present equipartition values, and transformed simultaneously to large galactic--scales by an inverse cascade promoted by resistive processes.
Keywords
Cite
@article{arxiv.0901.0116,
title = {Global simulations of galactic dynamo driven by cosmic-rays and exploding magnetized stars},
author = {Michał Hanasz and Dominik Wóltański and Kacper Kowalik and Rafał Pawłaszek},
journal= {arXiv preprint arXiv:0901.0116},
year = {2009}
}
Comments
2 pages, 2 figures, To be published in "Cosmic Magnetic Fields: From Planets, to Stars and Galaxies", K.G. Strassmeier, A.G. Kosovichev & J.E. Beckman, eds., Proc. IAU Symp. 259, CUP