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arXiv · 1802.00878

DECam Survey for Low-Mass Stars and Substellar Objects in the UCL and LCC Subgroups of the Sco-Cen OB Association (SCOCENSUS)

Fred E. Moolekamp·Eric E. Mamajek·David J. James·Kevin L. Luhman·Mark J. Pecaut·Stanmir A. Metchev·Cameron P. M. Bell·Sara R. Denbo
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Abstract

Using images taken with the Dark Energy Camera (DECam), the first extensive survey of low mass and substellar objects is made in the 15-20 Myr Upper Centaurus Lupus (UCL) and Lower Centaurus Crux (LCC) subgroups of the Scorpius Centaurus OB Association (Sco-Cen). Due to the size of our dataset (>2Tb) we developed an extensive open source set of python libraries to reduce our images, including astrometry, coaddition, and PSF photometry. Our survey consists of 29$\times$3 deg$^2$ fields in the UCL and LCC subgroups of Sco-Cen and the creation of a catalog with over 11 million point sources. We create a prioritized list of candidate for members in UCL and LCC, with 118 \emph{best} and another 348 \emph{good} candidates. We show that the luminosity and mass functions of our low mass and substellar candidates are consistent with measurements for the younger Upper Scorpius subgroup and estimates of a universal IMF, with spectral types ranging from M1 down to L1.

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Fred E. Moolekamp, Eric E. Mamajek, David J. James, Kevin L. Luhman, Mark J. Pecaut, Stanmir A. Metchev, Cameron P. M. Bell, Sara R. Denbo. 2018-02-02. DECam Survey for Low-Mass Stars and Substellar Objects in the UCL and LCC Subgroups of the Sco-Cen OB Association (SCOCENSUS). https://doi.org/10.1093/mnras/stz183

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