Mass Production of 2023 KMTNet Microlensing Planets. II: Two Planets and A Brown Dwarf

TL;DR

This paper reports the discovery and analysis of six microlensing planetary candidates from KMTNet data, including two confirmed planets and a brown dwarf, highlighting the effectiveness of the AnomalyFinder method and the degeneracy challenges in interpretation.

Contribution

It presents the identification and detailed modeling of six planetary candidates, including new planets and a brown dwarf, from the 2023 KMTNet data, and analyzes the degeneracy issues in microlensing signals.

Findings

Two planets with planetary mass ratios identified.

A brown dwarf companion detected.

Candidates from AnomalyFinder often show degeneracy.

Abstract

To expand the homogeneous microlensing planetary sample of the Korea Microlensing Telescope Network (KMTNet), we investigate six planetary candidates identified by the AnomalyFinder search in the 2023 prime-field data, namely KMT-2023-BLG-1592, OGLE-2023-BLG-0766, KMT-2023-BLG-0332, KMT-2023-BLG-0486, KMT-2023-BLG-0792, and OGLE-2023-BLG-1043. Light-curve modeling indicates that the first two events have planetary mass ratios of $\log q \sim -3.0$ and $-2.6$, while the third exhibits a brown dwarf mass ratio of $\log q \sim -1.4$. The remaining three events show the well-known degeneracy between the binary-lens single-source (2L1S) and single-lens binary-source (1L2S) interpretations. A Bayesian analysis yields companion masses of about 0.6 and 1.2 Jupiter masses for the two planetary systems, likely orbiting beyond the snow lines of M- or K-dwarf hosts. A review of the KMTNet planetary sample shows that candidates discovered by AnomalyFinder are significantly more likely to exhibit the 2L1S/1L2S degeneracy, consistent with the tendency of AnomalyFinder to detect subtler planetary signals.