Systematic Reanalysis of KMTNet microlensing events, Paper I: Updates of the Photometry Pipeline and a New Planet Candidate

Abstract

In this work, we update and develop algorithms for KMTNet tender-love care (TLC) photometry in order to create an new, mostly automated, TLC pipeline. We then start a project to systematically apply the new TLC pipeline to the historic KMTNet microlensing events, and search for buried planetary signals. We report the discovery of such a planet candidate in the microlensing event MOA-2019-BLG-421/KMT-2019-BLG-2991. The anomalous signal can be explained by either a planet around the lens star or the orbital motion of the source star. For the planetary interpretation, despite many degenerate solutions, the planet is most likely to be a Jovian planet orbiting an M or K dwarf, which is a typical microlensing planet. The discovery proves that the project can indeed increase the sensitivity of historic events and find previously undiscovered signals.

19 pages, 13 figures, 7 tables. Submitted to MNRAS

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Cited by in corpus (11)

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• Systematic KMTNet Planetary Anomaly Search. XII. Complete Sample of 2017 Subprime Field Planets
• A free-floating-planet microlensing event caused by a Saturn-mass object
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• KMT-2025-BLG-1616Lb: First Microlensing Bound Planet From DREAMS
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