KMT-2023-BLG-1431Lb: A New q &lt; 10<SUP>‑4</SUP> Microlensing Planet from a Subtle Signature

Bell, Aislyn; Zhang, Jiyuan; Zang, Weicheng; Jung, Youn Kil; Yee, Jennifer C.; Yang, Hongjing; Sumi, Takahiro; Udalski, Andrzej; Albrow, Michael D.; Chung, Sun-Ju; Gould, Andrew; Han, Cheongho; Hwang, Kyu-Ha; Ryu, Yoon-Hyun; Shin, In-Gu; Shvartzvald, Yossi; Cha, Sang-Mok; Kim, Dong-Jin; Kim, Seung-Lee; Lee, Chung-Uk; Lee, Dong-Joo; Lee, Yongseok; Park, Byeong-Gon; Pogge, Richard W.; KMTNet Collaboration; Tang, Yunyi; McCormick, Jennie; Dong, Subo; Liu, Zhuokai; de Almeida, Leandro; Mao, Shude; Maoz, Dan; Zhu, Wei; MAP and μFUN Follow-up Team; Abe, Fumio; Barry, Richard; Bennett, David P.; Bhattacharya, Aparna; Bond, Ian A.; Fujii, Hirosane; Fukui, Akihiko; Hamada, Ryusei; Hirao, Yuki; Silva, Stela Ishitani; Itow, Yoshitaka; Kirikawa, Rintaro; Kondo, Iona; Koshimoto, Naoki; Matsubara, Yutaka; Matsumoto, Sho; Miyazaki, Shota; Muraki, Yasushi; Okamura, Arisa; Lmschenk, Greg; Ranc, Clément; Rattenbury, Nicholas J.; Satoh, Yuki; Suzuki, Daisuke; Toda, Taiga; Tomoyoshi, Mio; Tristram, Paul J.; Vandorou, Aikaterini; Yama, Hibiki; Yamashita, Kansuke; MOA Collaboration; 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; OGLE Collaboration
Bibliographical reference

Publications of the Astronomical Society of the Pacific

Advertised on:
5
2024
Number of authors
78
IAC number of authors
1
Citations
1
Refereed citations
1
Description
The current studies of microlensing planets are limited by small number statistics. Follow-up observations of high-magnification microlensing events can efficiently form a statistical planetary sample. Since 2020, the Korea Microlensing Telescope Network (KMTNet) and the Las Cumbres Observatory (LCO) global network have been conducting a follow-up program for high-magnification KMTNet events. Here, we report the detection and analysis of a microlensing planetary event, KMT-2023-BLG-1431, for which the subtle (0.05 mag) and short-lived (5 hr) planetary signature was characterized by the follow-up from KMTNet and LCO. A binary-lens single-source (2L1S) analysis reveals a planet/host mass ratio of q = (0.72 ± 0.07) × 10‑4, and the single-lens binary-source (1L2S) model is excluded by Δχ 2 = 80. A Bayesian analysis using a Galactic model yields estimates of the host star mass of , the planetary mass of , and the lens distance of kpc. The projected planet-host separation of au or au, subject to the close/wide degeneracy. We also find that without the follow-up data, the survey-only data cannot break the degeneracy of central/resonant caustics and the degeneracy of 2L1S/1L2S models, showing the importance of follow-up observations for current microlensing surveys.