Abstract We report the analysis of four unambiguous planets and one possible planet from the subprime fields (Γ ≤ 1 hr−1) of the 2017 Korea Microlensing Telescope Network (KMTNet) microlensing survey, to complete the KMTNet AnomalyFinder planetary sample for the 2017 subprime fields. They are KMT-2017-BLG-0849, KMT-2017-BLG-1057, OGLE-2017-BLG-0364, and KMT-2017-BLG-2331 (unambiguous), as well as KMT-2017-BLG-0958 (possible). For the four unambiguous planets, the mean planet–host mass ratios,q, are (1.0, 1.2, 4.6, 13) × 10−4, the median planetary masses are (6.4, 24, 76, 171)M⊕, and the median host masses are (0.19, 0.57, 0.49, 0.40)M⊙, respectively, found from a Bayesian analysis. We have completed the Anomaly Finder planetary sample from the first 4 yr of KMTNet data (2016–2019), with 112 unambiguous planets in total, which nearly tripled the microlensing planetary sample. The “sub-Saturn desert” ( ) found in the 2018 and 2019 KMTNet samples is confirmed by the 2016 and 2017 KMTNet samples.
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This content will become publicly available on May 7, 2026
Systematic Reanalysis of KMTNet Microlensing Events. II. Two New Planets in Giant-source Events
Abstract In this work, we continue to apply the updated KMTNet tender-love care 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 areq ∼ 4 × 10−3andq ∼ 1 × 10−4, 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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- Award ID(s):
- 2108414
- PAR ID:
- 10654669
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- AAS Journals
- Date Published:
- Journal Name:
- The Astronomical Journal
- Volume:
- 169
- Issue:
- 6
- ISSN:
- 0004-6256
- Page Range / eLocation ID:
- 295
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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