The JCMT Gould Belt Survey: A First Look at the Auriga-California Molecular Cloud with SCUBA-2

H. Broekhoven-Fiene; B. C. Matthews; P. Harvey; H. Kirk; M. Chen; M. J. Currie; K. Pattle; J. Lane; J. Buckle; J. Di Francesco; E. Drabek-Maunder; D. Johnstone; D. S. Berry; M. Fich; J. Hatchell; T. Jenness; J. C. Mottram; D. Nutter; J. E. Pineda; C. Quinn; C. Salji; S. Tisi; M. R. Hogerheijde; D. Ward-Thompson; P. Bastien; D. Bresnahan; H. Butner; A. Chrysostomou; S. Coude; C. J. Davis; A. Duarte-Cabral; J. Fiege; P. Friberg; R. Friesen; G. A. Fuller; S. Graves; J. Greaves; J. Gregson; W. Holland; G. Joncas; J. M. Kirk; L. B. G. Knee; S. Mairs; K. Marsh; G. Moriarty-Schieven; C. Mowat; J. Rawlings; J. Richer; D. Robertson; E. Rosolowsky; D. Rumble; S. Sadavoy; H. Thomas; N. Tothill; S. Viti; G. J. White; C. D. Wilson; J. Wouterloot; J. Yates; M. Zhu

doi:10.3847/1538-4357/aa911f

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arXiv · 1801.08139

The JCMT Gould Belt Survey: A First Look at the Auriga-California Molecular Cloud with SCUBA-2

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Abstract

We present 850 and 450 micron observations of the dense regions within the Auriga-California molecular cloud using SCUBA-2 as part of the JCMT Gould Belt Legacy Survey to identify candidate protostellar objects, measure the masses of their circumstellar material (disk and envelope), and compare the star formation to that in the Orion A molecular cloud. We identify 59 candidate protostars based on the presence of compact submillimeter emission, complementing these observations with existing Herschel/SPIRE maps. Of our candidate protostars, 24 are associated with young stellar objects (YSOs) in the Spitzer and Herschel/PACS catalogs of 166 and 60 YSOs, respectively (177 unique), confirming their protostellar nature. The remaining 35 candidate protostars are in regions, particularly around LkHalpha 101, where the background cloud emission is too bright to verify or rule out the presence of the compact 70 micron emission that is expected for a protostellar source. We keep these candidate protostars in our sample but note that they may indeed be prestellar in nature. Our observations are sensitive to the high end of the mass distribution in Auriga-Cal. We find that the disparity between the richness of infrared star forming objects in Orion A and the sparsity in Auriga-Cal extends to the submillimeter, suggesting that the relative star formation rates have not varied over the Class II lifetime and that Auriga-Cal will maintain a lower star formation efficiency.

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H. Broekhoven-Fiene, B. C. Matthews, P. Harvey, H. Kirk, M. Chen, M. J. Currie, K. Pattle, J. Lane, J. Buckle, J. Di Francesco, E. Drabek-Maunder, D. Johnstone, D. S. Berry, M. Fich, J. Hatchell, T. Jenness, J. C. Mottram, D. Nutter, J. E. Pineda, C. Quinn, C. Salji, S. Tisi, M. R. Hogerheijde, D. Ward-Thompson, P. Bastien, D. Bresnahan, H. Butner, A. Chrysostomou, S. Coude, C. J. Davis, A. Duarte-Cabral, J. Fiege, P. Friberg, R. Friesen, G. A. Fuller, S. Graves, J. Greaves, J. Gregson, W. Holland, G. Joncas, J. M. Kirk, L. B. G. Knee, S. Mairs, K. Marsh, G. Moriarty-Schieven, C. Mowat, J. Rawlings, J. Richer, D. Robertson, E. Rosolowsky, D. Rumble, S. Sadavoy, H. Thomas, N. Tothill, S. Viti, G. J. White, C. D. Wilson, J. Wouterloot, J. Yates, M. Zhu. 2018-01-24. The JCMT Gould Belt Survey: A First Look at the Auriga-California Molecular Cloud with SCUBA-2. https://doi.org/10.3847/1538-4357%2Faa911f

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