HERUS: The Far-IR/Submm Spectral Energy Distributions of Local ULIRGs &
  Photometric Atlas
  We present the Herschel-SPIRE photometric atlas for a complete flux limited
sample of 43 local Ultraluminous Infrared Galaxies (ULIRGs), selected at
60${\mu}$m by IRAS, as part of the HERschel ULIRG Survey (HERUS). Photometry
observations were obtained using the SPIRE instrument at 250, 350 and
500${\mu}$m. We describe these observations, present the results, and combine
the new observations with data from IRAS to examine the far-IR spectral energy
distributions (SEDs) of these sources. We fit the observed SEDs of HERUS
objects with a simple parameterised modified black body model where temperature
and emissivity $\beta$ are free parameters. We compare the fitted values to
those of non-ULIRG local galaxies, and find, in agreement with earlier results,
that HERUS ULIRGs have warmer dust (median temperature T = 37.9+/-4.7 K
compared to 21.3+/-3.4 K) but a similar $\beta$ distribution (median $\beta$ =
1.7 compared to 1.8) to the Herschel reference sample (HRS, Cortese et al.,
2014) galaxies. Dust masses are found to be in the range of 10^7.5 to 10^9 Msun
significantly higher than that of Herschel Reference Sample (HRS) sources. We
compare our results for local ULIRGs with higher redshift samples selected at
250 and 850${\mu}$m. These latter sources generally have cooler dust and/or
redder 100-to-250 ${\mu}$m colours than our 60${\mu}$m-selected ULIRGs. We show
that this difference may in part be the result of the sources being selected at
different wavelengths rather than being a simple indication of rapid evolution
in the properties of the population.
