Transiting Planets

Monitoring of over 100 million stars with exquisite photometric precision will enable RGES to potentially discover between 60,000 and 200,000 transiting exoplanets. Most of these planets will be giants on close-in orbits, but Roman should also discover approximately 10,000 planets with small radii (< 4R_earth). A comprehensive, pixel-level simulation study was conducted by Wislon et al. 2023 to estimate the predicted yield of transiting planets by Roman, assuming recent survey designs and occurrence rates for transiting planets.

Caption: Example light curves for two simulated sources with transits injected at the pixel level. In each row of figures, the left panel shows the light curve (gray points), along with the injected signal before (black line) and after (blue line) adjusting for crowding. The right panels show a ∼2″ × 2″ cutout of the region surrounding the star of interest. Nearby stars brighter than F146 = 24 are denoted by a white “x,” with their sizes indicative of their brightness. The figure label gives relevant information on the simulated system, including its recovered significance (MES) and crowding (Γc)

Caption: The combined planet detection sensitivity via transit and microlensing in the Roman Galactic Bulge Time Domain Survey. The contours show the sum of the transit survey efficiency multiplied by the number of stars searched and the microlensing survey efficiency from Penny et al. (2019). The green/blue points show the sample of detected planets for one field of the GBTDS. The green points denote conservative requirements of >1 transit per season (>7 total), and the blue points denote liberal detection requirements of <1 transit per season (<7 total), including single-transiting systems.