Low surface brightness science with LSST: the opportunities and the dangers

The low surface brightness (LSB) universe remains one of the last bastions of astronomical discovery. Only recently has this regime become open to observation, with advances in both optics and data reduction techniques, and still, most of the LSB regime remains the purview of small, dedicated surveys of individual targets. LSST, with its unprecedented breadth and depth--expected to reach surface brightnesses below 29 mag arcsec^2 over 20,000 deg^2 of sky--provides a remarkable opportunity to study this regime in detail, by finally offering statistically significant samples of dwarf galaxies, tidal features, and intrahalo light across a wide range of environments. This opportunity, however, comes with risk: LSB science is extremely sensitive to both observing strategy and to the data reduction pipeline, and what works for LSB science may not work for all of the survey's key science goals. Large dither patterns are needed to improve flat-fielding accuracy and reduce the impact of scattered light, but could also reduce integration times per unit area in deep-drilling fields. Simple, low-order sky models are necessary to remove night-sky emission from images without over-subtracting unmasked LSB flux as part of the sky, but leaving this flux intact could result in blending of objects over large angular scales. We discuss the difficulties inherent to doing LSB science in large-scale, multi-purpose surveys like LSST, the risks these difficulties pose to LSB science, and the efforts we are making toward ensuring that all varieties of LSB science are possible with LSST, so that we do not squander the immense opportunity the survey provides.