Bibcode
Zang, Weicheng; Hwang, Kyu-Ha; Udalski, Andrzej; Wang, Tianshu; Zhu, Wei; Sumi, Takahiro; Yee, Jennifer C.; Gould, Andrew; Mao, Shude; Zhang, Xiangyu; Albrow, Michael D.; Chung, Sun-Ju; Han, Cheongho; Jung, Youn Kil; Ryu, Yoon-Hyun; Shin, In-Gu; Shvartzvald, Yossi; 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; Skowron, Jan; Poleski, Radoslaw; Szymański, Michał K.; Soszyński, Igor; Pietrukowicz, Paweł; Kozłowski, Szymon; Ulaczyk, Krzysztof; Rybicki, Krzysztof A.; Iwanek, Patryk; Wrona, Marcin; Gromadzki, Mariusz; Bond, Ian A.; Abe, Fumio; Barry, Richard; Bennett, David P.; Bhattacharya, Aparna; Donachie, Martin; Fujii, Hirosane; Fukui, Akihiko; Hirao, Yuki; Itow, Yoshitaka; Kirikawa, Rintaro; Kondo, Iona; Koshimoto, Naoki; Li, Man Cheung Alex; Matsubara, Yutaka; Muraki, Yasushi; Miyazaki, Shota; Olmschenk, Greg; Ranc, Clément; Rattenbury, Nicholas J.; Satoh, Yuki; Shoji, Hikaru; Ishitani Silva, Stela; Suzuki, Daisuke; Tanaka, Yuzuru; Tristram, Paul J.; Yamawaki, Tsubasa; Yonehara, Atsunori; Beichman, Charles A.; Bryden, Geoffery; Calchi Novati, Sebastiano; Carey, Sean; Gaudi, B. Scott; Henderson, Calen B.; Johnson, Samson; Spitzer Team
Bibliographical reference
The Astronomical Journal
Advertised on:
10
2021
Citations
40
Refereed citations
37
Description
In order to exhume the buried signatures of "missing planetary caustics" in Korea Microlensing Telescope Network (KMTNet) data, we conducted a systematic anomaly search of the residuals from point-source point-lens fits, based on a modified version of the KMTNet EventFinder algorithm. This search revealed the lowest-mass-ratio planetary caustic to date in the microlensing event OGLE-2019-BLG-1053, for which the planetary signal had not been noticed before. The planetary system has a planet-host mass ratio of q = (1.25 ± 0.13) × 10-5. A Bayesian analysis yielded estimates of the mass of the host star, ${M}_{\mathrm{host}}={0.61}_{-0.24}^{+0.29}\,{M}_{\odot }$ , the mass of its planet, ${M}_{\mathrm{planet}}={2.48}_{-0.98}^{+1.19}\,{M}_{\oplus }$ , the projected planet-host separation, ${a}_{\perp }={3.4}_{-0.5}^{+0.5}$ au, and the lens distance, ${D}_{{\rm{L}}}={6.8}_{-0.9}^{+0.6}$ kpc. The discovery of this very-low-mass-ratio planet illustrates the utility of our method and opens a new window for a large and homogeneous sample to study the microlensing planet-host mass ratio function down to q ~ 10-5.