Prospects for detection of catastrophic collisions in debris disks

We investigate the prospects for detecting dust from two-body collisions during the late stages of planet formation at 1 - 150 AU. We develop an analytic model to describe the formation of a dusty cloud of debris and use numerical coagulation and N-body calculations to predict observable signals from these events. In a minimum mass solar nebula, collisions of 100 - 1000 km objects at distances of 3 - 5 AU or less from the parent star are observable at mid-IR wavelengths as bright clumps or rings of dust. At 24 mu m, the clumps are similar to 0.1 - 1 mag brighter than emission from dust in the background debris disk. In edge-on systems, dusty clumps produce eclipses with depths of less than or similar to 1.0 mag that last for similar to 100 orbital periods. Large-scale surveys for transits from exosolar planets, using satellites such as Kepler, can plausibly detect these eclipses and provide important constraints on the terrestrial environment for ages of less than or similar to 100 - 300 Myr.