Submillimetre observations of the two-component magnetic field in M82 [GA]

http://arxiv.org/abs/2105.01989


We observed the starburst galaxy M82 in 850$\mu$m polarised light with the POL-2 polarimeter on the James Clerk Maxwell Telescope (JCMT). We interpret our observed polarisation geometry as tracing a two-component magnetic field: a poloidal component aligned with the galactic ‘superwind’, extending to a height $\sim 350$ pc above and below the central bar; and a spiral-arm-aligned, or possibly toroidal, component in the plane of the galaxy, which dominates the 850$\mu$m polarised light distribution at galactocentric radii $\gtrsim 2$ kpc. Comparison of our results with recent HAWC+ measurements of the field in the dust entrained by the M82 superwind suggests that the superwind breaks out from the central starburst at $\sim 350$ pc above the plane of the galaxy.

Read this paper on arXiv…

K. Pattle, W. Gear, M. Redman, et. al.
Thu, 6 May 21
24/55

Comments: 5 pages, 5 figures, accepted by Monthly Notices of the Royal Astronomical Society (MNRAS)