Detection of Exoplanet as a Binary Source of Microlensing Events in WFIRST Survey

Abstract

We investigate the possibility of exoplanet detection orbiting source stars in microlensing events through WFIRST observations. We perform a Monto Carlo simulation on the detection rate of exoplanets via microlensing, assuming that each source star has at least one exoplanet. The exoplanet can reflect part of the light from the parent star or emit internal thermal radiation. In this new detection channel, we use microlensing as an amplifier to magnify the reflection light from the planet. In the literature, this mode of detecting exoplanets has been investigated much less than the usual mode in which the exoplanets are considered as one companion in binary lens events. Assuming $72$ days of observation per season with the cadence of $15$ minutes, we find the probability of rocky planet detection with this method to be virtually zero. However, there is non-zero probability, for the detection of Jovian planets. We estimate the detection rates of the exoplanets by this method, using WFIRST observation to be $0.012\%$ in single lens events and $0.9\%$ in the binary lens events.

Accepted for publication to MNRAS Main Journal. 7 pages, 3 figures

References in corpus (7)

• Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report
• Most 1.6 Earth-Radius Planets are not Rocky
• The phase-dependent Infrared brightness of the extrasolar planet upsilon Andromedae b
• Interstellar Extinction Law toward the Galactic Center II: V, J, H, and Ks Bands
• Thermal Emission from Transiting Very-Hot Jupiters: Prospects for Ground-based Detection at Optical Wavelengths
• Optimal Survey Strategies and Predicted Planet Yields for the Korean Microlensing Telescope Network
• Planet formation around stars of various masses: Hot super-Earths

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• Revealing Short-period Exoplanets and Brown Dwarfs in the Galactic Bulge using the Microlensing Xallarap Effect with the \textit{Nancy Grace Roman Space Telescope}
• Numerically studying the degeneracy problem in extreme finite-source microlensing events
• Detecting the inner regions of discs around sources of microlensing with Roman Space Telescope