An SDSS Survey For Resolved Milky Way Satellite Galaxies. I. Detection Limits

We present the detection limits of a new survey for resolved low surfacebrightness satellite galaxies to the Milky Way, based on the Sloan Digital SkySurvey (SDSS). Our survey exploits SDSS's major strengths (multi-colorphotometry, depth, large-scale, and uniformity) by combining filter smoothingwith limits in both magnitude and color space to search for low surfacebrightness galaxies and stellar counterparts to the Compact High VelocityClouds out to the Milky Way's virial radius (350 kpc). Our calculated detectionlimits for a purely old stellar population vary with galaxy size and distancebetween mu_{V,0} = 26.7 and 30.1 mag/sq ''. These limits will allow us todetect systems whose surface brightnesses are .5-3.9 mag/sq '' fainter thanSextans, the lowest surface brightness Local Group member known. Our survey notonly is sensitive to lower surface brightness stellar populations than possiblewith previous Local Group surveys, but will also allow us to make an unbiasedand well defined assessment of the completeness of the observed Local Groupgalaxy luminosity function, so that we may compare the results with thepredictions of various structure formation scenarios.Comment: 12 pages, 6 Figures, accepted for publication in A