Expansion of Planet Detection Methods in Next‐Generation Microlensing Surveys

Abstract

We classify various types of planetary lensing signals and the methods for detecting them. We estimate the relative frequencies of planet detections by various methods, with special emphasis on new methods to be provided by future lensing experiments that will continuously survey wide fields at high cadence using very large format imaging cameras. From this investigation, we find that the fraction of wide-separation planets that would be discovered through the new methods of detecting planetary signals as independent and repeating events would be substantial. We estimate that the fraction of planets detectable through the new methods would comprise ~15%-30% of all planets, depending on the models of planetary separation distribution and the mass ratios of the planets. Considering that a significant fraction of planets might exist as free-floating planets, the frequency of detections through the new methods would be even higher. With the addition of the new methods, future lensing surveys will greatly expand the range of planets that can be detected.