Magnetohydrodynamic turbulence in supernova remnants
Abstract
We present estimates of the angular power spectra of the synchrotron radiation intensity fluctuations at 6 and 20 cm for the shell type supernova remnant Cas A and the filled-centre Crab supernova remnant. We find that the intensity fluctuations of both sources have a power law power spectrum with index -3.24 +/- 0.03. This power law power spectrum is consistent with the magnetohydrodynamic turbulence in the synchrotron emitting plasma. For Cas A, there is a break in the power spectrum and the power law index changes from -3.2 to -2.2 at large angular scale. This transition occurs at an angular scale that corresponds to the shell thickness of Cas A. We interpret this as a transition from three dimensional turbulence to two dimensional turbulence on scales that are respectively smaller and larger than the shell thickness.
Keywords
Cite
@article{arxiv.0811.1466,
title = {Magnetohydrodynamic turbulence in supernova remnants},
author = {Nirupam Roy and Somnath Bharadwaj and Prasun Dutta and Jayaram N. Chengalur},
journal= {arXiv preprint arXiv:0811.1466},
year = {2009}
}
Comments
6 pages, 1 table, 5 figures. Corrected minor typos. Accepted for publication in MNRAS Letters. The definitive version will be available at http://www.blackwell-synergy.com/