Orbital Motion During Gravitational Lensing Events

TL;DR

This paper investigates how orbital motion influences gravitational lensing events, enhancing the detection and analysis of planetary and binary systems through various observational platforms.

Contribution

It extends previous models to include orbital motion effects, demonstrating their significance in current and future gravitational lensing observations.

Findings

Orbital motion significantly affects a large fraction of lensing light curves.

Orbital motion broadens the range of binaries detectable via lensing.

Upcoming observational missions will increasingly utilize orbital motion effects.

Abstract

Gravitational lensing events provide unique opportunities to discover and study planetary systems and binaries. Here we build on previous work to explore the role that orbital motion can play in both identifying and learning more about multiple-mass systems that serve as gravitational lenses. We find that a significant fraction of planet-lens and binary-lens light curves are influenced by orbital motion. Furthermore, the effects of orbital motion extend the range of binaries for which lens multiplicity can be discovered and studied. Orbital motion will play an increasingly important role as observations with sensitive photometry, such as those made by the space missions Kepler, Transiting Exoplanet Survey Satellite, (TESS), and WFIRST discover gravitational lensing events. Similarly, the excellent astrometric measurements made possible by GAIA will allow it to study the effects of orbital motion. Frequent observations, such as those made possible with the Korean Microlensing Telescope Network, KMTNet, will also facilitate the study of orbital motion during gravitational lensing events. Finally, orbital motion will typically play a significant role in the characteristics of lensing events in which the passage of a specific nearby star in front of a background star can be predicted.