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Title: OGLE-2019-BLG-1180Lb: Discovery of a Wide-orbit Jupiter-mass Planet around a Late-type Star
Abstract

We report on the discovery and analysis of the planetary microlensing event OGLE-2019-BLG-1180 with a planet-to-star mass ratioq∼ 0.003. The event OGLE-2019-BLG-1180 has unambiguous cusp-passing and caustic-crossing anomalies, which were caused by a wide planetary caustic withs≃ 2, wheresis the star–planet separation in units of the angular Einstein radiusθE. Thanks to well-covered anomalies by the Korea Micorolensing Telescope Network (KMTNet), we measure both the angular Einstein radius and the microlens parallax in spite of a relatively short event timescale oftE= 28 days. However, because of a weak constraint on the parallax, we conduct a Bayesian analysis to estimate the physical lens parameters. We find that the lens system is a super-Jupiter-mass planet ofMp=1.750.51+0.53MJorbiting a late-type star ofMh=0.550.26+0.27Mat a distanceDL=6.11.3+0.9kpc. The projected star–planet separation isa=5.191.23+0.90au, which means that the planet orbits at about four times the snow line of the host star. Considering the relative lens–source proper motion ofμrel= 6 mas yr−1, the lens will be separated from the source by 60 mas in 2029. At that time one can measure the lens flux from adaptive optics imaging of Keck or a next-generation 30 m class telescope. OGLE-2019-BLG-1180Lb represents a growing population of wide-orbit planets detected by KMTNet, so we also present a general investigation into prospects for further expanding the sample of such planets.

 
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NSF-PAR ID:
10474467
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astronomical Journal
Volume:
166
Issue:
6
ISSN:
0004-6256
Format(s):
Medium: X Size: Article No. 253
Size(s):
["Article No. 253"]
Sponsoring Org:
National Science Foundation
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