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arXiv · 1608.04353

The JCMT and Herschel Gould Belt Surveys: A comparison of SCUBA-2 and Herschel data of dense cores in the Taurus dark cloud L1495

Derek Ward-Thompson·Kate Pattle·Jason Kirk·Ken Marsh·Jane Buckle·Jennifer Hatchell·David Nutter·Matt Griffin·James Di Francesco·Philippe André·Sylvie Beaulieu·David Berry·Hannah Broekhoven-Fiene·Malcolm Currie·Michel Fich·Timothy Jenness·Doug Johnstone·Helen Kirk·Joseph Mottram·Jaime Pineda·Ciera Quinn·Sarah Sadavoy·Carl Salji·Sam Tisi·Sarah Walker-Smith·Glenn White·Tracey Hill·Vera Könyves·Pedro Palmeirim·Stefano Pezzuto
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Abstract

We present a comparison of SCUBA-2 850-$\mu$m and Herschel 70--500-$\mu$m observations of the L1495 filament in the Taurus Molecular Cloud with the goal of characterising the SCUBA-2 Gould Belt Survey (GBS) data set. We identify and characterise starless cores in three data sets: SCUBA-2 850-$\mu$m, Herschel 250-$\mu$m, and Herschel 250-$\mu$m spatially filtered to mimic the SCUBA-2 data. SCUBA-2 detects only the highest-surface-brightness sources, principally detecting protostellar sources and starless cores embedded in filaments, while Herschel is sensitive to most of the cloud structure, including extended low-surface-brightness emission. Herschel detects considerably more sources than SCUBA-2 even after spatial filtering. We investigate which properties of a starless core detected by Herschel determine its detectability by SCUBA-2, and find that they are the core's temperature and column density (for given dust properties). For similar-temperature cores, such as those seen in L1495, the surface brightnesses of the cores are determined by their column densities, with the highest-column-density cores being detected by SCUBA-2. For roughly spherical geometries, column density corresponds to volume density, and so SCUBA-2 selects the densest cores from a population at a given temperature. This selection effect, which we quantify as a function of distance, makes SCUBA-2 ideal for identifying those cores in Herschel catalogues that are closest to forming stars. Our results can now be used by anyone wishing to use the SCUBA-2 GBS data set.

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Derek Ward-Thompson, Kate Pattle, Jason Kirk, Ken Marsh, Jane Buckle, Jennifer Hatchell, David Nutter, Matt Griffin, James Di Francesco, Philippe André, Sylvie Beaulieu, David Berry, Hannah Broekhoven-Fiene, Malcolm Currie, Michel Fich, Timothy Jenness, Doug Johnstone, Helen Kirk, Joseph Mottram, Jaime Pineda, Ciera Quinn, Sarah Sadavoy, Carl Salji, Sam Tisi, Sarah Walker-Smith, Glenn White, Tracey Hill, Vera Könyves, Pedro Palmeirim, Stefano Pezzuto. 2016-08-15. The JCMT and Herschel Gould Belt Surveys: A comparison of SCUBA-2 and Herschel data of dense cores in the Taurus dark cloud L1495. https://doi.org/10.1093/mnras/stw1978

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