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arXiv · 2503.19471

Systematic Reanalysis of KMTNet Microlensing Events, Paper II: Two New Planets in Giant-Source Events

Hongjing Yang·Jennifer C. Yee·Jiyuan Zhang·Chung-Uk Lee·Dong-Jin Kim·Ian A. Bond·Andrzej Udalski·Kyu-Ha Hwang·Weicheng Zang·Qiyue Qian·Andrew Gould·Shude Mao·Michael D. Albrow·Sun-Ju Chung·Cheongho Han·Youn Kil Jung·Yoon-Hyun Ryu·In-Gu Shin·Yossi Shvartzvald·Sang-Mok Cha·Hyoun-Woo Kim·Seung-Lee Kim·Dong-Joo Lee·Yongseok Lee·Byeong-Gon Park·Richard W. Pogge·Fumio Abe·Ken Bando·David P. Bennett·Aparna Bhattacharya·Akihiko Fukui·Ryusei Hamada·Shunya Hamada·Naoto Hamasaki·Yuki Hirao·Stela Ishitani Silva·Yoshitaka Itow·Naoki Koshimoto·Yutaka Matsubara·Shota Miyazaki·Yasushi Muraki·Tutumi Nagai·Kansuke Nunota·Greg Olmschenk·Clément Ranc·Nicholas J. Rattenbury·Yuki Satoh·Takahiro Sumi·Daisuke Suzuki·Sean K. Terry·Paul . J. Tristram·Aikaterini Vandorou·Hibiki Yama·Przemek Mróz·Jan Skowron·Radoslaw Poleski·Michał K. Szymański·Igor Soszyński·Paweł Pietrukowicz·Szymon Kozłowski·Krzysztof Ulaczyk·Krzysztof A. Rybicki·Patryk Iwanek·Marcin Wrona
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Abstract

In this work, we continue to apply the updated KMTNet tender-love care (TLC) photometric pipeline to historical microlensing events. We apply the pipeline to a subsample of events from the KMTNet database, which we refer to as the giant source sample. Leveraging the improved photometric data, we conduct a systematic search for anomalies within this sample. The search successfully uncovers four new planet-like anomalies and recovers two previously known planetary signals. After detailed analysis, two of the newly discovered anomalies are confirmed as clear planets: KMT-2019-BLG-0578 and KMT-2021-BLG-0736. Their planet-to-host mass ratios are $q\sim4\times10^{-3}$ and $q\sim1\times10^{-4}$, respectively. Another event, OGLE-2018-BLG-0421 (KMT-2018-BLG-0831), remains ambiguous. Both a stellar companion and a giant planet in the lens system could potentially explain the observed anomaly. The anomaly signal of the last event, MOA-2022-BLG-038 (KMT-2022-BLG-2342), is attributed to an extra source star. Within this sample, our procedure doubles the number of confirmed planets, demonstrating a significant enhancement in the survey sensitivity.

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Hongjing Yang, Jennifer C. Yee, Jiyuan Zhang, Chung-Uk Lee, Dong-Jin Kim, Ian A. Bond, Andrzej Udalski, Kyu-Ha Hwang, Weicheng Zang, Qiyue Qian, Andrew Gould, Shude Mao, Michael D. Albrow, Sun-Ju Chung, Cheongho Han, Youn Kil Jung, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Sang-Mok Cha, Hyoun-Woo Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Fumio Abe, Ken Bando, David P. Bennett, Aparna Bhattacharya, Akihiko Fukui, Ryusei Hamada, Shunya Hamada, Naoto Hamasaki, Yuki Hirao, Stela Ishitani Silva, Yoshitaka Itow, Naoki Koshimoto, Yutaka Matsubara, Shota Miyazaki, Yasushi Muraki, Tutumi Nagai, Kansuke Nunota, Greg Olmschenk, Clément Ranc, Nicholas J. Rattenbury, Yuki Satoh, Takahiro Sumi, Daisuke Suzuki, Sean K. Terry, Paul . J. Tristram, Aikaterini Vandorou, Hibiki Yama, Przemek Mróz, Jan Skowron, Radoslaw Poleski, Michał K. Szymański, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof Ulaczyk, Krzysztof A. Rybicki, Patryk Iwanek, Marcin Wrona. 2025-04-26. Systematic Reanalysis of KMTNet Microlensing Events, Paper II: Two New Planets in Giant-Source Events. https://doi.org/10.3847/1538-3881%2Fadc73e

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