OGLE-2018-BLG-0567Lb and OGLE-2018-BLG-0962Lb: Two Microlensing Planets through the Planetary-caustic Channel

• Published in: The Astronomical journal 2021-06, Vol.161 (6), p.293
• Main Authors: Kil Jung, Youn, Han, Cheongho, Udalski, Andrzej, Gould, Andrew, Yee, Jennifer C., Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Zhu, Wei, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Hyoun-Woo, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Mróz, Przemek, Szymański, Michał K., Skowron, Jan, Poleski, Radek, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Ulaczyk, Krzystof, Rybicki, Krzysztof A., Iwanek, Patryk, Wrona, Marcin
• Format: Article
• Language: English
• Subjects: Alkalies; Anomalies; Astronomy; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; Bayesian analysis; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPUTERIZED SIMULATION; CROSS SECTIONS; CROSSING-OVER; Galactic bulge; Gravitational microlensing; Gravitational microlensing exoplanet detection; Microlenses; Planet detection; Planetary systems; PLANETS; Polls & surveys
• ISSN: 0004-6256; 1538-3881; 1538-3881
• DOI: 10.3847/1538-3881/abf8bd

We present the analyses of two microlensing events, OGLE-2018-BLG-0567 and OGLE-2018-BLG-0962. In both events, the short-lasting anomalies were densely and continuously covered by two high-cadence surveys. The light-curve modeling indicates that the anomalies are generated by source crossings over the planetary caustics induced by planetary companions to the hosts. The estimated planet/host separation (scaled to the angular Einstein radius θ E ) and mass ratio are ( s , q × 10 3 ) = (1.81 ± 0.02, 1.24 ± 0.07) and ( s , q × 10 3 ) = (1.25 ± 0.03, 2.38 ± 0.08), respectively. From Bayesian analyses, we estimate the host and planet masses as ( M h , M p ) = ( 0.25 − 0.13 + 0.27 M ⊙ , 0.32 − 0.17 + 0.34 M J ) and ( M h , M p ) = ( 0.54 − 0.28 + 0.33 M ⊙ , 1.34 − 0.70 + 0.82 M J ) , respectively. These planetary systems are located at a distance of 7.06 − 1.15 + 0.93 kpc for OGLE-2018-BLG-0567 and 6.50 − 1.75 + 1.06 kpc for OGLE-2018-BLG-0962, suggesting that they are likely to be near the Galactic bulge. The two events prove the capability of current high-cadence surveys for finding planets through the planetary-caustic channel. We find that most published planetary-caustic planets are found in Hollywood events in which the source size strongly contributes to the anomaly cross-section relative to the size of the caustic.