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    MOA-2022-BLG-249Lb: Nearby microlensing super-Earth planet detected from high-cadence surveys
    (EDP Sciences for The European Southern Observatory, 2023-06) Han C; Gould A; Jung YK; Bond IA; Zang W; Chung S-J; Albrow MD; Hwang K-H; Ryu Y-H; Shin I-G; Shvartzvald Y; Yang H; Yee JC; Cha S-M; Kim D; Kim D-J; Kim S-L; Lee C-U; Lee D-J; Lee Y; Park B-G; Pogge RW; Mao S; Zhu W; Abe F; Barry R; Bennett DP; Bhattacharya A; Fujii H; Fukui A; Hamada R; Hirao Y; Ishitani Silva S; Itow Y; Kirikawa R; Kondo I; Koshimoto N; Matsubara Y; Matsumoto S; Miyazaki S; Muraki Y; Okamura A; Olmschenk G; Ranc C; Rattenbury NJ; Satoh Y; Sumi T; Suzuki D; Toda T; Tomoyoshi M; Tristram PJ; Vandorou A; Yama H; Yamashita K
    Aims. We investigate the data collected by the high-cadence microlensing surveys during the 2022 season in search of 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 one day, with a maximum deviatio Methods. We analyzed 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). Results. We find that the anomaly is better explained by the planetary model than the binary-source model. We identified two solutions rooted in the inner-outer degeneracy and for both of them, the estimated planet-To-host mass ratio, q ~ 8 A-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 of (4.83 ± 1.44) M·, orbits a low-mass host star, with a mass of (0.18 ± 0.05) M·, lying in the Galactic disk at a distance of (2.00 ± 0.42) kpc. The planet detection demonstrates the elevated microlensing sensitivity of the current high-cadence lensing surveys to low-mass planets.
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    KMT-2022-BLG-0475Lb and KMT-2022-BLG-1480Lb: Microlensing ice giants detected via the non-caustic-crossing channel
    (EDP Sciences, France, 2023-08) Han C; Lee C-U; Bond IA; Zang W; Chung S-J; Albrow MD; Gould A; Hwang K-H; Jung YK; Ryu Y-H; Shin I-G; Shvartzvald Y; Yang H; Yee JC; Cha S-M; Kim D; Kim D-J; Kim S-L; Lee D-J; Lee Y; Park B-G; Pogge RW; Mao S; Zhu W; Abe F; Barry R; Bennett DP; Bhattacharya A; Fujii H; Fukui A; Hamada R; Hirao Y; Ishitani Silva S; Itow Y; Kirikawa R; Kondo I; Koshimoto N; Matsubara Y; Miyazaki S; Muraki Y; Olmschenk G; Ranc C; Rattenbury NJ; Satoh Y; Sumi T; Suzuki D; Toda T; Tomoyoshi M; Tristram PJ; Vandorou A; Yama H; Yamashita K
    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 A-104 for KMT-2022-BLG-0475L and q 4.3 A-104 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) = (0.430.23+0.35, 1.730.92+1.42, 2.030.38+0.25) for KMT-2022-BLG-0475L and (0.180.09+0.16, 1.820.92+1.60, 1.220.14+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.