Maja Kierdorf, Max Planck Institut für Radio Astronomie

​Probing the Magnetized Disk - Halo Transition Region in M51 via Wideband Polarimetry

An excellent laboratory for studying  well ordered magnetic fields is the grand design face-on spiral galaxy M51. Due to wavelength-dependent Faraday depolarization, polarized emission at different radio frequencies gives a picture of the galaxy at different depths: previous observations at L-band (1-2GHz) probes the halo region while at C-band (4-8GHz) the polarized emission comes from the disk region of M51. In this talk, I will present new observations of M51 with the Very Large Array at S-band (2-4GHz), where currently no polarization data exists, to shed new light on the transition region between disk and halo. The wide frequency coverage and high spatial resolution of about 7 arcsec allow us to probe the disk-halo transition region to get detailed information on the magnetic field structure in the plane of the sky and on the vertical magnetic field component in this unknown layer.

Previous models applied to the polarized emission shows different behavior for different magnetic field configurations in the disk and halo. I will show our observational results of the transition layer, which is critical for our understanding on the origin of large-scale halo fields and how they are connected to the underlying galactic disk.

Category Seminar
Location: Onsala rymdobservatorium, space observatory, Seminarierummet
Starts: 10 October, 2018, 10:00
Ends: 10 October, 2018, 11:00

Published: Fri 17 Aug 2018.