OGLE-2018-BLG-0567Lb and OGLE-2018-BLG-0962Lb: Two Microlensing Planets through the Planetary-caustic Channel
Han, Cheongho; Udalski, Andrzej; Lee, Chung-Uk; Zang, Weicheng; Albrow, Michael D.; Chung, Sun-Ju; Gould, Andrew; Hwang, Kyu-Ha; Jung, Youn Kil; Ryu, Yoon-Hyun; Shvartzvald, Yossi; Shin, In-Gu; Yee, Jennifer C.; Cha, Sang-Mok; Kim, Dong-Jin; Kim, Seung-Lee; Lee, Dong-Joo; Lee, Yongseok; Park, Byeong-Gon; Pogge, Richard W.; Mróz, Przemek; Szymański, Michał K.; Skowron, Jan; Soszyński, Igor; Pietrukowicz, Paweł; Kozłowski, Szymon; Rybicki, Krzysztof A.; Iwanek, Patryk; Wrona, Marcin; KMTNet Collaboration; Poleski, Radek; Kim, Hyoun-Woo; Zhu, Wei; OGLE Collaboration; Ulaczyk, Krzystof
South Korea, Poland, United States, Germany, New Zealand, Israel, Canada, China, United Kingdom
Abstract
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 θE) and mass ratio are (s, q × 103) = (1.81 ± 0.02, 1.24 ± 0.07) and (s, q × 103) = (1.25 ± 0.03, 2.38 ± 0.08), respectively. From Bayesian analyses, we estimate the host and planet masses as $({M}_{{\rm{h}}},{M}_{{\rm{p}}})=({0.25}_{-0.13}^{+0.27}\,{M}_{\odot },{0.32}_{-0.17}^{+0.34}\,{M}_{{\rm{J}}})$ and $({M}_{{\rm{h}}},{M}_{{\rm{p}}})=({0.54}_{-0.28}^{+0.33}\,{M}_{\odot },{1.34}_{-0.70}^{+0.82}\,{M}_{{\rm{J}}})$ , respectively. These planetary systems are located at a distance of ${7.06}_{-1.15}^{+0.93}\,\mathrm{kpc}$ for OGLE-2018-BLG-0567 and ${6.50}_{-1.75}^{+1.06}\,\mathrm{kpc}$ 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.