Feb 06, 2014

Tim Robishaw, Dominion Radio Astrophysical Observatory

"Measuring Magnetic Fields Near and Far via the Zeeman Effect "

The Zeeman effect is the only observational tool that allows us to directly
measure the magnetic field strength and direction in the interstellar
medium.  We provide an overview of ongoing projects in which we are using
the Zeeman splitting of the 21-cm line and the 18-cm hydroxyl (OH)
transitions in order to probe astrophysical magnetic fields.  We will
highlight the first detection of extragalactic Zeeman splitting in the OH
megamaser emission from starburst galaxies.  Results will be shown from a
southern survey of Zeeman splitting in OH masers in our Milky Way's spiral
arms that suggest field reversals relative to the field directions probed
by Faraday rotation.  We will also discuss previous measurements of the
Zeeman effect in Galactic 21-cm radio emission, some of the instrumental
challenges involved in such measurements, and plans for a large-scale
survey underway on the 64-m Parkes telescope and the 26-m John A. Galt
Telescope at the Dominion Radio Astrophysical Observatory.

Event Details

Feb 06, 2014


4421 Sterling Hall

Coffee served at 3:30pm; talk starts at 3:45pm

Speaker Host:
Ann Mao

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