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arXiv · 2111.03755

OGLE-2019-BLG-0468Lb,c: two microlensing giant planets around a G-type star

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

With the aim of interpreting anomalous lensing events with no suggested models, we conducted a project of reinvestigating microlensing data in and before the 2019 season. In this work, we report a multi-planet system OGLE-2019-BLG-0468L found from the project. The light curve of the lensing event OGLE-2019-BLG-0468, which consists of three distinctive anomaly features, could not be explained by the usual binary-lens or binary-source interpretation. We find a solution explaining all anomaly features with a triple-lens interpretation, in which the lens is composed of two planets and their host, making the lens the fourth multi-planet system securely found by microlensing. The two planets have masses $\sim 3.4~M_{\rm J}$ and $\sim 10.2~M_{\rm J}$, and they are orbiting around a G-type star with a mass $\sim 0.9~M_\odot$ and a distance $\sim 4.4$ kpc. The host of the planets is most likely responsible for the light of the baseline object, although the possibility for the host to be a companion to the baseline object cannot be ruled out.

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Cheongho Han, Andrzej Udalski, Chung-Uk Lee, Doeon Kim, Wei Zhu, Michael D. Albrow, Sun-Ju Chung, Andrew Gould, Kyu-Ha Hwang, Youn Kil Jung, Hyoun-Woo Kim, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Weicheng Zang, Sang-Mok Cha, Dong-Jin Kim, Seung-Lee Kim, Dong-Joo Lee, Yongseok Lee, Byeong-Gon Park, Richard W. Pogge, Chun-Hwey Kim, Woong-Tae Kim, Przemek Mróz, Michał K. Szymański, Jan Skowron, Radosław Poleski, Igor Soszyński, Paweł Pietrukowicz, Szymon Kozłowski, Krzysztof A. Rybicki, Patryk Iwanek, Krzysztof Ulaczyk, Marcin Wrona, Mariusz Gromadzki, David Buckley, Subo Dong, Ali Luo. 2021-11-05. OGLE-2019-BLG-0468Lb,c: two microlensing giant planets around a G-type star. https://doi.org/10.1051/0004-6361%2F202142327

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