Planck intermediate results. LV. Reliability and thermal properties of
  high-frequency sources in the Second Planck Catalogue of Compact Sources
  We describe an extension of the most recent version of the Planck Catalogue
of Compact Sources (PCCS2), produced using a new multi-band Bayesian Extraction
and Estimation Package (BeeP). BeeP assumes that the compact sources present in
PCCS2 at 857 GHz have a dust-like spectral energy distribution, which leads to
emission at both lower and higher frequencies, and adjusts the parameters of
the source and its SED to fit the emission observed in Planck's three highest
frequency channels at 353, 545, and 857 GHz, as well as the IRIS map at 3000
GHz. In order to reduce confusion regarding diffuse cirrus emission, BeeP's
data model includes a description of the background emission surrounding each
source, and it adjusts the confidence in the source parameter extraction based
on the statistical properties of the spatial distribution of the background
emission. BeeP produces the following three new sets of parameters for each
source: (a) fits to a modified blackbody (MBB) thermal emission model of the
source; (b) SED-independent source flux densities at each frequency considered;
and (c) fits to an MBB model of the background in which the source is embedded.
BeeP also calculates, for each source, a reliability parameter, which takes
into account confusion due to the surrounding cirrus. We define a
high-reliability subset (BeeP/base), containing 26 083 sources (54.1 per cent
of the total PCCS2 catalogue), the majority of which have no information on
reliability in the PCCS2. The results of the BeeP extension of PCCS2, which are
made publicly available via the PLA, will enable the study of the thermal
properties of well-defined samples of compact Galactic and extra-galactic dusty
sources.
