The JCMT Gould Belt Survey: First results from SCUBA-2 observations of the Cepheus Flare Region

Abstract

We present observations of the Cepheus Flare obtained as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Legacy Survey (GBLS) with the SCUBA-2 instrument. We produce a catalogue of sources found by SCUBA-2, and separate these into starless cores and protostars. We determine masses and densities for each of our sources, using source temperatures determined by the Herschel Gould Belt Survey. We compare the properties of starless cores in four different molecular clouds: L1147/58, L1172/74, L1251 and L1228. We find that the core mass functions for each region typically show shallower-than-Salpeter behaviour. We find that L1147/58 and L1228 have a high ratio of starless cores to Class II protostars, while L1251 and L1174 have a low ratio, consistent with the latter regions being more active sites of current star formation, while the former are forming stars less actively. We determine that, if modelled as thermally-supported Bonnor-Ebert spheres, most of our cores have stable configurations accessible to them. We estimate the external pressures on our cores using archival ${}^{13}$CO velocity dispersion measurements and find that our cores are typically pressure-confined, rather than gravitationally bound. We perform a virial analysis on our cores, and find that they typically cannot be supported against collapse by internal thermal energy alone, due primarily to the measured external pressures. This suggests that the dominant mode of internal support in starless cores in the Cepheus Flare is either non-thermal motions or internal magnetic fields.

Accepted for publication by MNRAS, 29 pages, 16 figures, 8 tables

References in corpus (8)

• The Mass Distribution and Lifetime of Prestellar Cores in Perseus, Serpens, and Ophiuchus
• SCUBA-2: iterative map-making with the Sub-Millimetre User Reduction Facility
• A SCUBA survey of Orion, the low-mass end of the core mass function
• The James Clerk Maxwell Telescope Legacy Survey of Nearby Star-forming Regions in the Gould Belt
• The initial conditions of star formation VIII: an observational study of the Ophiuchus cloud L1688 and implications for the prestellar core mass function
• The JCMT and Herschel Gould Belt Surveys: A comparison of SCUBA-2 and Herschel data of dense cores in the Taurus dark cloud L1495
• The JCMT Gould Belt Survey: SCUBA-2 observations of circumstellar disks in L 1495
• Molecular Line Observations of the Small Protostellar Group L1251B

Cited by in corpus (14)

• The Green Bank Ammonia Survey: Dense Cores Under Pressure in Orion A
• How do stars gain their mass? A JCMT/SCUBA-2 Transient Survey of Protostars in Nearby Star Forming Regions
• Magnetic Properties of Star-Forming Dense Cores
• Herschel Gould Belt Survey Observations of Dense Cores in the Cepheus Flare Clouds
• The Green Bank Ammonia Survey: A Virial Analysis of Gould Belt Clouds in Data Release 1
• The Green Bank Ammonia Survey: Observations of Hierarchical Dense Gas Structures in Cepheus-L1251
• The outbursting protostar 2MASS~22352345+7517076 and its environment
• A search for cloud cores affected by shocked carbon chain chemistry in L1251
• Characterization of dense Planck clumps observed with Herschel and SCUBA-2
• Dust emission, extinction, and scattering in LDN 1642
• Filaments in the OMC-3 cloud and uncertainties in estimates of filament profiles
• Prestellar Cores in Turbulent Clouds: Properties of Critical Cores
• The JCMT Gould Belt Survey Complete Core Catalogue: Core mass function variations between nearby molecular clouds
• Interstellar filament detection and characterization: methods and implications for studies of magnetized interstellar medium