Ilse

Theoretical models predict that core-collapse supernovae (CCSNe)
can be efficient dust producers (0.1-1 M$_{text{sun}}$) and potentially responsible
for most of the dust production in the early Universe. Observational
evidence for this dust production efficiency has remained limited.
Herschel observations from 70-500 microns of the 335-year old Cassiopeia A
have indicated the presence of $sim$0.1 M$_{text{sun}}$ of cool (T$sim$35 K) dust interior to
the reverse shock (Barlow et al. 2010), while Dunne et al. (2009) have
claimed a detection of $sim$1 M$_{text{sun}}$ of cold ($sim$20 K) dust, based on SCUBA
850-micron polarimetric data. At sub-millimeter wavelengths, the supernova
dust emission is heavily contaminated by interstellar dust emission and by
the synchrotron radiation from the SNR.

We present the first spatially resolved analysis of the infrared and
submillimeter emission of Cas,A at better than 1 parsec resolution, based
on our Herschel PACS and SPIRE 70-500um images. We used our PACS IFU and
SPIRE FTS spectra to remove the contaminating emission from bright lines
(e.g. [OIII]88, [CII]158). We updated the spectral index of the
synchrotron emission based on recent Planck data, and extrapolated this
synchrotron spectrum from a 3.7 mm VLA image to infrared/submillimeter
wavelengths. We modeled the interstellar dust emission using a Galactic
dust emission template from Jones et al. (2013), while the ISM dust mass
is scaled to reproduce the continuum emission in the SPIRE FTS spectra at
wavelengths $>$ 650 micron (after subtraction of synchrotron emission). The
UV radiation field that illuminates the ISM dust was constrained through
PDR modelling of the [CI] 1-0, 2-1 and CO 4-3 lines observed in the SPIRE
FTS spectra, and was found to range between 0.3 G$_{text{0}}$ and 1.0 G$_{text{0}}$ in units
of the Draine IS radiation field.

Within the uncertainties of the radiation field that illuminates the ISM
material and the observational errors, we detect a dust mass of up to 0.8
M$_{text{sun}}$ in Cas,A, with an average temperature of 30 K, in the region interior
to the reverse shock. Our SN dust mass map has a rather smooth appearance,
which suggests that dust formed uniformly throughout the ejecta. A Cas A
dust mass of up to 0.8 M$_{text{sun}}$ is in the same range as the $sim$0.7 M$_{text{sun}}$ of dust
found in SN 1987A (Matsuura et al. 2015) and the $sim$0.2 M$_{text{sun}}$ of dust found
in the Crab Nebula (Gomez et al. 2012; Owen & Barlow 2015). With these
dust masses core-collapse supernovae can potentially account for the very
large large masses of dust that have been observed in some high redshift
galaxies.