Two Jupiter-Mass Planets Discovered by the KMTNet Survey in 2017

Abstract

We report two microlensing events, KMT-2017-BLG-1038 and KMT-2017-BLG-1146 that are caused by planetary systems. These events were discovered by KMTNet survey observations from the $2017$ bulge season. The discovered systems consist of a planet and host star with mass ratios, $5.3_{-0.4}^{+0.2}\times 10^{-3}$ and $2.0_{-0.1}^{+0.6}\times 10^{-3}$, respectively. Based on a Bayesian analysis assuming a Galactic model without stellar remnant hosts, we find that the planet, KMT-2017-BLG-1038Lb, is a super Jupiter-mass planet ($M_{\mathrm{p}}=2.04_{-1.15}^{+2.02}{M}_{\mathrm{J}}$) orbiting a mid-M dwarf host ($M_{\mathrm{h}}=0.37_{-0.20}^{+0.36}{M}_{\odot }$) that is located at $6.01_{-1.72}^{+1.27}$ kpc toward the Galactic bulge. The other planet, KMT-2017-BLG-1146Lb, is a sub Jupiter-mass planet ($M_{\mathrm{p}}=0.71_{-0.42}^{+0.80}{M}_{\mathrm{J}}$) orbiting a mid-M dwarf host ($M_{\mathrm{h}}=0.33_{-0.20}^{+0.36}{M}_{\odot }$) at a distance toward the Galactic bulge of $6.50_{-2.00}^{+1.38}$ kpc. Both are potentially gaseous planets that are beyond their hosts' snow lines. These typical microlensing planets will be routinely discovered by second-generation microlensing surveys, rapidly increasing the number of detections.

8 pages, 10 figures, 2 tables, accepted for publication in AJ