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The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. I. Chamaeleon II Observed with MIPS

K. E. Young·P. M. Harvey·T. Y. Brooke·N. Chapman·J. Kauffmann·F. Bertoldi·S. -P. Lai·J. Alcala'·T. L. Bourke·W. Spiesman·L. E. Allen·G. A. Blake·N. J. Evans II·D. W. Koerner·L. G. Mundy·P. C. Myers·D. L. Padgett·A. Salinas·A. I. Sargent·K. R. Stapelfeldt·P. Teuben·E. F. van Dishoeck·Z. Wahhaj
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Abstract

We present maps of over 1.5 square degrees in Chamaeleon (Cha) II at 24, 70, and 160 micron observed with the Spitzer Space Telescope Multiband Imaging Photometer for Spitzer (MIPS) and a 1.2 square degree millimeter map from SIMBA on the Swedish-ESO Submillimetre Telescope (SEST). The c2d Spitzer Legacy Team's data reduction pipeline is described in detail. Over 1500 24 micron sources and 41 70 micron sources were detected by MIPS with fluxes greater than 10-sigma. More than 40 potential YSOs are identified with a MIPS and 2MASS color-color diagram and by their spectral indices, including two previously unknown sources with 24 micron excesses. Our new SIMBA millimeter map of Cha II shows that only a small fraction of the gas is in compact structures with high column densities. The extended emission seen by MIPS is compared with previous CO observations. Some selected interesting sources, including two detected at 1 mm, associated with Cha II are discussed in detail and their SEDs presented. The classification of these sources using MIPS data is found to be consistent with previous studies.

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K. E. Young, P. M. Harvey, T. Y. Brooke, N. Chapman, J. Kauffmann, F. Bertoldi, S. -P. Lai, J. Alcala', T. L. Bourke, W. Spiesman, L. E. Allen, G. A. Blake, N. J. Evans II, D. W. Koerner, L. G. Mundy, P. C. Myers, D. L. Padgett, A. Salinas, A. I. Sargent, K. R. Stapelfeldt, P. Teuben, E. F. van Dishoeck, Z. Wahhaj. 2005-03-30. The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. I. Chamaeleon II Observed with MIPS. https://doi.org/10.1086/430597

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