The Lunar Occultation Observer (LOCO): A Hard X-Ray All-Sky Survey Mission Concept

The hard X-ray sky has tremendous potential for future discoveries and is one of the last electromagnetic regimes without a sensitive all-sky survey. A new approach to such a survey is to utilize the Moon as an occulting disk. The Lunar Occultation Observer (LOCO) mission concept, based on this lunar occultation technique (LOT) and incorporating advanced inorganic scintillators as a detection medium, represents a sensitive and cost effective option for NASA´s Beyond Einstein Black Hole Finder Probe or a future Explorer-class mission. We present the motivating factors for the LOT, outline developmental details and simulation results, as well as give preliminary estimates for source detection sensitivity.