arXiv 0807.33452008-07-25astro-ph

The Invisibles: A Detection Algorithm to Trace the Faintest Milky Way Satellites

Shane Walsh, Beth Willman, Helmut Jerjen

备注：: 22 pages, submitted to AJ. You can find a version with full resolution figures at http://msowww.anu.edu.au/~jerjen/SMS_papers.html. Replacement version includes small clarification of discussion and astro-ph numbers in references
DOI：: 10.1088/0004-6256/137/1/450

英文摘要：

[Abridged] A specialized data mining algorithm has been developed using wide-field photometry catalogues, enabling systematic and efficient searches for resolved, extremely low surface brightness satellite galaxies in the halo of the Milky Way (MW). Tested and calibrated with the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) we recover all fifteen MW satellites recently detected in SDSS, six known MW/Local Group dSphs in the SDSS footprint, and 19 previously known globular and open clusters. In addition, 30 point source overdensities have been found that correspond to no cataloged objects. The detection efficiencies of the algorithm have been carefully quantified by simulating more than three million model satellites embedded in star fields typical of those observed in SDSS, covering a wide range of parameters including galaxy distance, scale-length, luminosity, and Galactic latitude.

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