KMT-2022-BLG-0475Lb and KMT-2022-BLG-1480Lb: Microlensing ice giants detected via the non-caustic-crossing channel

Han, Cheongho; Lee, Chung-Uk; Bond, Ian A.; Zang, Weicheng; Chung, Sun-Ju; Albrow, Michael D.; Gould, Andrew; Hwang, Kyu-Ha; Jung, Youn Kil; Ryu, Yoon-Hyun; Shin, In-Gu; Shvartzvald, Yossi; Yang, Hongjing; Yee, Jennifer C.; Cha, Sang-Mok; Kim, Doeon; Kim, Dong-Jin; Kim, Seung-Lee; Lee, Dong-Joo; Lee, Yongseok; Park, Byeong-Gon; Pogge, Richard W.; Mao, Shude; Zhu, Wei; Abe, Fumio; Barry, Richard; Bennett, David P.; Bhattacharya, Aparna; Fujii, Hirosame; Fukui, Akihiko; Hamada, Ryusei; Hirao, Yuki; Ishitani Silva, Stela; Itow, Yoshitaka; Kirikawa, Rintaro; Kondo, Iona; Koshimoto, Naoki; Matsubara, Yutaka; Miyazaki, Shota; Muraki, Yasushi; Olmschenk, Greg; Ranc, Clément; Rattenbury, Nicholas J.; Satoh, Yuki; Sumi, Takahiro; Suzuki, Daisuke; Toda, Taiga; Tomoyoshi, Mio; Tristram, Paul J.; Vandorou, Aikaterini; Yama, Hibiki; Yamashita, Kansuke
Bibliographical reference

Astronomy and Astrophysics

Advertised on:
8
2023
Number of authors
52
IAC number of authors
1
Citations
2
Refereed citations
1
Description

Aims: We investigate the microlensing data collected in the 2022 season from high-cadence microlensing surveys in order to find weak signals produced by planetary companions to lenses.
Methods: From these searches, we find that two lensing events, KMT-2022-BLG-0475 and KMT-2022-BLG-1480, exhibit weak short-term anomalies. From a detailed modeling of the lensing light curves, we determine that the anomalies are produced by planetary companions with a mass ratio to the primary of q ~ 1.8 × 10−4 for KMT-2022-BLG-0475L and q ~ 4.3 × 10−4 for KMT-2022-BLG-1480L.
Results: We estimate that the host and planet masses and the projected planet-host separation are (Mh/M⊙, Mp/MU, a⊥/au) = (0.43−0.23+0.35, 1.73−0.92+1.42, 2.03−0.38+0.25) for KMT-2022-BLG-0475L and (0.18−0.09+0.16, 1.82−0.92+1.60, 1.22−0.14+0.15) for KMT-2022-BLG-1480L, where MU denotes the mass of Uranus. The two planetary systems have some characteristics in common: the primaries of the lenses are early-mid M dwarfs that lie in the Galactic bulge, and the companions are ice giants that lie beyond the snow lines of the planetary systems.