Abstract
Abstract
We report on the discovery and analysis of the planetary microlensing event OGLE-2019-BLG-1180 with a planet-to-star mass ratio q ∼ 0.003. The event OGLE-2019-BLG-1180 has unambiguous cusp-passing and caustic-crossing anomalies, which were caused by a wide planetary caustic with s ≃ 2, where s is the star–planet separation in units of the angular Einstein radius θ
E. 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 of t
E = 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 of
M
p
=
1.75
−
0.51
+
0.53
M
J
orbiting a late-type star of
M
h
=
0.55
−
0.26
+
0.27
M
⊙
at a distance
D
L
=
6.1
−
1.3
+
0.9
kpc
. The projected star–planet separation is
a
⊥
=
5.19
−
1.23
+
0.90
au
, which means that the planet orbits at about four times the snow line of the host star. Considering the relative lens–source proper motion of μ
rel = 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.
Funder
Korea Astronomy and Space Science Institute
National Science Foundation
National Research Foundation of Korea
Publisher
American Astronomical Society
Subject
Space and Planetary Science,Astronomy and Astrophysics