First [CII] map taken with SOFIA FIFI-LS published

Thursday, September 27, 2018

The CARS team published the first results from the SOFIA FIFI-LS instrument of spatially-resolved [CII] 158micron emission in a nearby luminous AGN host galaxy at redshift z~0.04. The work is led by Dr. G. Busch from the University of Cologne and shows that the [CII] emission largely follows the expectations from the amount and distribution of ongoing star formation in the host galaxy as mapped with the VLT-MUSE integral-field spectrograph at high spatial resolution in the optical. It shows that AGN do not necessarily impact the [CII] excitation, but a larger sample is currently under investigation to confirm this result. The SOFIA FIFI-LS instrument also detected [CII] emission far beyond the host galaxy which has an unknown origin. We speculated that neutral gas in the outskirts of the disc is excited either by the UV background or a diffuse radiation field from the galaxy itself. In summary, the CARS team has successfully shown that the SOFIA airborne observatory is able to capture [CII] emission not only in our Milky Way but also in nearby galaxies out to significant redshifts. The article will appear in the upcoming SOFIA focus issue of the Astrophysical Journal Letters.

Comparison of the predicted [CII] map from Ha observed with VLT-MUSE and the real [CII] map observed with SOFIA FIFI-LS. The elongated [CII] structure of the prominent star forming bar in this galaxy is well visible even at the limited spatial resolution of SOFIA. The [CII] surface brightness follows nicely previous relations established for star forming galaxies observed with Herschel.