We as Co-Chairs of the Galaxies SC Low Surface Brightness Working Group [Sarah Brough and Aaron Watkins] and our DM representative [Lee Kelvin] would like to propose organising a breakout session on low surface brightness astronomy with LSST. This is an important regime, holding much of LSST’s discovery space, and is a key area of current research that will be uniquely expanded upon by LSST’s combination of depth and area. For instance, galaxy clusters contain vast numbers of stars in diffuse light between the galaxies, which account for a significant fraction of the cluster mass. The definitive LSST sample can capture enough of these systems to quantify the amount and spatial extent of this intra-cluster light in a more systematic fashion across, cosmic time, than ever previously possible. We will be able to characterize the stellar halos that surround nearby galaxies and unveil structures therein, such as tidal features and density inhomogeneities produced by galaxy mergers and interactions. These features, which are signposts of the hierarchical formation processes, will provide critical clues to the formation history on a galaxy-by-galaxy basis. LSST will also enable the most complete census of dwarf galaxies at cosmological distances (which dominate the galaxy number density) and of low surface or ultra-diffuse galaxies to date. As well as the study of Galactic stellar streams, diffuse extended Galactic emission, low surface brightness satellites of the Milky Way, and optical properties of Galactic cirrus or emission line regions like PNe or SN remnants.
In order to best detect and analyse the low surface brightness light in LSST images there are a number of key preparatory tasks we need to undertake due to the importance of background subtraction in preserving this light. With LSST commissioning just around the corner and much effort underway, this is the ideal time to discuss the efforts made towards these preparatory tasks and discuss strategies adopted on common problems, to ensure that we are prepared for when data arrives. With low surface brightness science already being done with precursor surveys, the session will also include presentations on recent scientific results.