Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2010-07-06
Physics in Canada, Volume 64, No. 4 (Oct.-Dec. (Fall) 2008), pages 215-225
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
11 pages including 7 figures. This was an invited contribution to a special issue on Astrophysics in the Canadian Association
Scientific paper
An electromagnetic wave can be uniquely characterized by the four Stokes parameters: I, Q, U, and V. Typical observations in astronomy rely solely on total intensity measurements of the incoming radiation (Stokes I). However, a significant amount of information both about the emitting region and the propagation path is carried in the remaining Stokes parameters. These data provide a means to observe parts of the interstellar medium which remain invisible in Stokes I, at any wavelength. For example, when an electromagnetic wave propagates through a region containing free electrons and a magnetic field, the plane of polarisation of the wave will rotate - an effect recorded only in Stokes Q and U. The interstellar medium of the Galaxy is such a region, containing free electrons (observed as HII) and a magnetic field of a few microgauss. By imaging in Stokes Q and U we are able to observe signatures of magnetic field perturbations from the small scale (tens of pc) to the large scale (kpc). In this paper, we review the status of Canadian polarisation studies of cosmic magnetic fields and discuss the leading role Canada is playing in polarsation studies around the world.
Brown Jo-Anne C.
Landecker Tom L.
Stil Jeroen M.
No associations
LandOfFree
Visualizing the Invisible using Polarisation Observations 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 Visualizing the Invisible using Polarisation Observations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Visualizing the Invisible using Polarisation Observations will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-344712