| |
 |
| Paper: |
The Polarization Signatures of Old Planetary Nebulae in the
Canadian Galactic Plane Survey |
| Volume: |
438, The Dynamic Interstellar Medium: A Celebration of the Canadian Galactic Plane Survey |
| Page: |
268 |
| Authors: |
Ransom, R. R.; Kothes, R.; Landecker, T. L.; Wolleben, a. M. |
| Abstract: |
We present Canadian Galactic Plane Survey (CGPS) polarization images
at 1420 MHz centered on two old planetary nebulae (PNe), Sh 2-216 and
DeHt 5. Faraday rotation of the diffuse synchrotron background
emission in the extended shells of these nebulae is readily observed
in the polarization images. In the case of Sh 2-216, we use estimates
of electron density and path length to derive the line-of-sight
component of the magnetic field in the optically bright north-east
portion of the nebula. We interpret our observations via a simple
model which describes a deflected and slightly compressed interstellar
field around Sh 2-216. In the case of the fast-moving
(∼60 km s–1) DeHt 5, we focus on a tail of
ionized gas, which starts at the back edge of DeHt 5 and runs away
from the nebula in a direction roughly opposite that of the
sky-projected space velocity. We believe this tail to be the
signature of ionized material ram-pressure stripped first during an
interaction between the asymptotic giant branch (AGB) progenitor and
the interstellar medium (ISM) and more recently during an interaction
between DeHt 5 and the ISM. |
|
|
|
|
|
