* Astronomy

Title: The Spitzer c2d Survey of Large, Nearby, Interstellar Clouds. IV. Lupus Observed with MIPS
Authors: Nicholas L. Chapman, Shih-Ping Lai, Lee G. Mundy, Neal J. Evans II, Timothy Y. Brooke, Lucas A. Cieza, William J. Spiesman, Luisa M. Rebull, Karl R. Stapelfeldt, Alberto Noriega-Crespo, Lauranne Lanz, Lori E. Allen, Geoffrey A. Blake, Tyler L. Bourke, Paul M. Harvey, Tracy L. Huard, Jes K. Jørgensen, David W. Koerner, Philip C. Myers, Deborah L. Padgett, Annelia I. Sargent, Peter Teuben, Ewine F. van Dishoeck, Zahed Wahhaj, Kaisa E. Young

We present maps of 7.78 square degrees of the Lupus molecular cloud complex at 24, 70, and 160\:\mu m. They were made with the Spitzer Space Telescope's Multiband Imaging Photometer for Spitzer (MIPS) instrument as part of the Spitzer Legacy Program, ''From Molecular Cores to Planet-Forming Disks'' (c2d). The maps cover three separate regions in Lupus, denoted I, III, and IV. We discuss the c2d pipeline and how our data processing differs from it. We compare source counts in the three regions with two other data sets and predicted star counts from the Wainscoat model. This comparison shows the contribution from background galaxies in Lupus I. We also create two colour magnitude diagrams using the 2MASS and MIPS data. From these results, we can identify background galaxies and distinguish them from probable young stellar objects. The sources in our catalogues are classified based on their spectral energy distribution (SED) from 2MASS and Spitzer wavelengths to create a sample of young stellar object candidates. From 2MASS data, we create extinction maps for each region and note a strong correspondence between the extinction and the 160\:\mu m emission. The masses we derived in each Lupus cloud from our extinction maps are compared to masses estimated from ^{13}CO and C^{18}O and found to be similar to our extinction masses in some regions, but significantly different in others. Finally, based on our colour-magnitude diagrams, we selected 12 of our reddest candidate young stellar objects for individual discussion. Five of the 12 appear to be newly-discovered YSOs.

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