Type |
Conference Paper |
Names |
Bryan M. Gaensler, M. Haverkorn, B. Burkhart, K. J. Newton-McGee, R. D. Ekers, A. Lazarian, N. M. McClure-Griffiths, T. Robishaw, J. M. Dickey, A. J. Green |
Proceedings Title |
Bulletin of the American Astronomical Society |
Conference Name |
American Astronomical Society, AAS Meeting #219, #349.04 |
Date |
January 1, 2012 |
Short Title |
Snakes in the Plane |
URL |
http://adsabs.harvard.edu/abs/2012AAS...21934904G |
Library Catalog |
NASA ADS |
Abstract |
The interstellar medium (ISM) of the Milky Way consists of gas and dust
at a range of temperatures and pressures, and provides the raw material
from which stars and planets form. Astronomers have developed a
sophisticated understanding of the ISM as a multi-phase, magnetized,
turbulent medium. However, observations have lacked the sensitivity and
resolution to directly image the small-scale structure associated with
turbulent motions in the diffuse ISM. Radio polarimetry is a promising
avenue for further progress, because Faraday rotation of linearly
polarized radio signals provides a very sensitive probe of fluctuations
in magnetic field and ionized gas density. Here we present a new way of
processing images of linearly polarized radio emission from the ISM, in
which we derive the gradient of the Stokes vector (Q,U). This provides
the first direct image of supersonic turbulence in the ISM, manifested
as a complex filamentary web of sharp density jumps. Application of the
polarization gradient to both simulations and observations can allow the
measurement of currently unconstrained parameters of interstellar
turbulence such as the Mach number, Reynolds number and magnetic field
strength. |