Paper

MOA-2022-BLG-249Lb: Nearby microlensing super-Earth planet detected from high-cadence surveys

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

2023

Overview

We investigate the data collected by the high-cadence microlensing surveys during the 2022 season in search for planetary signals appearing in the light curves of microlensing events. From this search, we find that the lensing event MOA-2022-BLG-249 exhibits a brief positive anomaly that lasted for about 1 day with a maximum deviation of \\(\\sim 0.2\\)~mag from a single-source single-lens model. We analyze the light curve under the two interpretations of the anomaly: one originated by a low-mass companion to the lens (planetary model) and the other originated by a faint companion to the source (binary-source model). It is found that the anomaly is better explained by the planetary model than the binary-source model. We identify two solutions rooted in the inner--outer degeneracy, for both of which the estimated planet-to-host mass ratio, \\(q\\sim 8\\times 10^{-5}\\), is very small. With the constraints provided by the microlens parallax and the lower limit on the Einstein radius, as well as the blend-flux constraint, we find that the lens is a planetary system, in which a super-Earth planet, with a mass \\((4.83\\pm 1.44)~M_\\oplus\\), orbits a low-mass host star, with a mass \\((0.18\\pm 0.05)~M_\\odot\\), lying in the Galactic disk at a distance \\((2.00\\pm 0.42)\\)~kpc. The planet detection demonstrates the elevated microlensing sensitivity of the current high-cadence lensing surveys to low-mass planets.

• Publisher: Cornell University Library, arXiv.org
• Subject: Companion stars / Extrasolar planets / Galactic disk / Light curve / Microlenses / Parallax / Planet detection / Planetary systems