Three sub-Jovian-mass microlensing planets: MOA-2022-BLG-563Lb, KMT-2023-BLG-0469Lb, and KMT-2023-BLG-0735Lb

¹ Department of Physics, Chungbuk National University, Cheongju 28644, Republic of Korea
e-mail: cheongho@astroph.chungbuk.ac.kr
² Korea Astronomy and Space Science Institute, Daejon 34055, Republic of Korea
³ Korea University of Science and Technology, Korea, (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea
⁴ Institute of Natural and Mathematical Science, Massey University, Auckland 0745, New Zealand
⁵ Max-Planck-Institute for Astronomy, Königstuhl 17, 69117 Heidelberg, Germany
⁶ Department of Astronomy, Ohio State University, 140 W. 18th Ave., Columbus, OH 43210, USA
⁷ University of Canterbury, Department of Physics and Astronomy, Private Bag 4800, Christchurch 8020, New Zealand
⁸ Center for Astrophysics | Harvard & Smithsonian, 60 Garden St., Cambridge, MA 02138, USA
⁹ Department of Particle Physics and Astrophysics, Weizmann Institute of Science, Rehovot 76100, Israel
¹⁰ Department of Astronomy, Tsinghua University, Beijing 100084, PR China
¹¹ School of Space Research, Kyung Hee University, Yongin, Kyeonggi 17104, Republic of Korea
¹² Institute for Space-Earth Environmental Research, Nagoya University, Nagoya 464-8601, Japan
¹³ Code 667, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
¹⁴ Department of Astronomy, University of Maryland, College Park, MD 20742, USA
¹⁵ Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
¹⁶ Instituto de Astrofísica de Canarias, Vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
¹⁷ Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
¹⁸ Department of Physics, The Catholic University of America, Washington, DC 20064, USA
¹⁹ Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210, Japan
²⁰ Sorbonne Université, CNRS, UMR 7095, Institut d’Astrophysique de Paris, 98 bis bd Arago, 75014 Paris, France
²¹ Department of Physics, University of Auckland, Private Bag 92019, Auckland, New Zealand
²² University of Canterbury Mt. John Observatory, PO Box 56, Lake Tekapo 8770, New Zealand

Received: 12 September 2023
Accepted: 19 January 2024

Abstract

Aims. We analyze the anomalies appearing in the light curves of the three microlensing events MOA-2022-BLG-563, KMT-2023-BLG-0469, and KMT-2023-BLG-0735. The anomalies exhibit common short-term dip features that appear near the peak.

Methods. From the detailed analyses of the light curves, we find that the anomalies were produced by planets accompanied by the lenses of the events. For all three events, the estimated mass ratios between the planet and host are on the order of 10⁻⁴: q ~ 8 × 10⁻⁴ for MOA-2022-BLG-563L, q ~ 2.5 × 10⁻⁴ for KMT-2023-BLG-0469L, and q ~ 1.9 × 10⁻⁴ for KMT-2023-BLG-0735L. The interpretations of the anomalies are subject to a common inner-outer degeneracy, which causes ambiguity when estimating the projected planet-host separation.

Results. We estimated the planet mass, M_p, host mass, M_h, and distance, D_L, to the planetary system by conducting Bayesian analyses using the observables of the events. The estimated physical parameters of the planetary systems are (M_h/M_⊙, M_p/M_J, D_L/kpc) = (0.48_−0.30^+0.36, 0.40_−0.25^+0.31, 6.53_−1.57^+1.12) for MOA-2022-BLG-563L, (0.47_−0.26^+0.35, 0.124_−0.067^+0.092, 7.07_−1.19^+1.03) for KMT-2023-BLG-0469L, and (0.62_−0.35^+0.34, 0.125_−0.070^+0.068, 6.26_−1.67^+1.27) for KMT-2023-BLG-0735L. According to the estimated parameters, all planets are cold planets with projected separations that are greater than the snow lines of the planetary systems, they have masses that lie between the masses of Uranus and Jupiter of the Solar System, and the hosts of the planets are main-sequence stars that are less massive than the Sun. In all cases, the planetary systems are more likely to be in the bulge with probabilities P_bulge = 64%, 73%, and 56% for MOA-2022-BLG-563, KMT-2023-BLG-0469, and KMT-2023-BLG-0735, respectively.