Predicting the self-lensing population in optical surveys

The vast majority of binaries containing a compact object and regular star spend most their time in quiescent state where no strong interactions occur between components. Detection these is extremely challenging only few candidates have been detected through optical spectroscopy. Self-lensing represents new means detecting objects binaries, gravitational lensing the light from visible component by produces periodic flares. Here we show that current planned large-area surveys can detect significant number ($\sim 100$-$10,000$s) self-lensing provide insights into properties lenses. We many predicted population observable will be observed with multiple flares; this both improves chances detection also immediately distinguishes them chance-alignment micro-lensing events. Through investigate long - but previously hidden stages binary evolution consequently constraints on evolutionary models which impact nature double mergers.