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arXiv · 2112.02414

Systematic KMTNet Planetary Anomaly Search, Paper III: One Wide-Orbit Planet And Two Stellar Binaries

Hanyue Wang·Weicheng Zang·Wei Zhu·Kyu-Ha Hwang·Andrzej Udalski·Andrew Gould·Cheongho Han·Michael D. Albrow·Sun-Ju Chung·Youn Kil Jung·Doeon Kim·Yoon-Hyun Ryu·In-Gu Shin·Yossi Shvartzvald·Jennifer C. Yee·Sang-Mok Cha·Dong-Jin Kim·Hyoun-Woo Kim·Seung-Lee Kim·Chung-Uk Lee·Dong-Joo Lee·Yongseok Lee·Byeong-Gon Park·Richard W. Pogge·Radoslaw Poleski·Przemek Mróz·Jan Skowron·Michał K. Szymański·Igor Soszyński·Paweł Pietrukowicz·Szymon Kozłowski·Krzysztof Ulaczyk·Krzysztof A. Rybicki·Patryk Iwanek·Marcin Wrona·Mariusz Gromadzki·Hongjing Yang·Shude Mao·Xiangyu Zhang
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Abstract

Only a few wide-orbit planets around old stars have been detected, which limits our statistical understanding of this planet population. Following the systematic search for planetary anomalies in microlensing events found by the Korea Microlensing Telescope Network (KMTNet), we present the discovery and analysis of three events that were initially thought to contain wide-orbit planets. The anomalous feature in the light curve of OGLE-2018-BLG-0383 is caused by a planet with mass ratio $q=2.1\times 10^{-4}$ and a projected separation $s=2.45$. This makes it the lowest mass-ratio microlensing planet at such wide orbits. The other two events, KMT-2018-BLG-0998 and OGLE-2018-BLG-0271, are shown to be stellar binaries ($q>0.1$) with rather close ($s<1$) separations. We briefly discuss the properties of known wide-orbit microlensing planets and show that the survey observations are crucial in discovering and further statistically constraining such a planet population.

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Hanyue Wang, Weicheng Zang, Wei Zhu, Kyu-Ha Hwang, Andrzej Udalski, Andrew Gould, Cheongho Han, Michael D. Albrow, Sun-Ju Chung, Youn Kil Jung, Doeon Kim, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Chung-Uk Lee, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Radoslaw Poleski, Przemek Mróz, Jan Skowron, Michał K. Szymański, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona, Mariusz Gromadzki, Hongjing Yang, Shude Mao, Xiangyu Zhang. 2021-12-04. Systematic KMTNet Planetary Anomaly Search, Paper III: One Wide-Orbit Planet And Two Stellar Binaries. https://doi.org/10.1093/mnras%2Fstab3581

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