MOA-2007-BLG-400 A Super-Jupiter-mass Planet Orbiting a Galactic Bulge K-dwarf Revealed by Keck Adaptive Optics Imaging

被引：23

作者：

Bhattacharya, Aparna ^{[1
,2
]}

Bennett, David P. ^{[1
,2
]}

Beaulieu, Jean Philippe ^{[3
,4
]}

Bond, Ian A. ^{[5
]}

Koshimoto, Naoki ^{[6
,7
]}

Lu, Jessica R. ^{[8
]}

Blackman, Joshua W. ^{[4
]}

Vandorou, Aikaterini ^{[4
]}

Terry, Sean K. ^{[8
]}

Batista, Virginie ^{[3
]}

Marquette, Jean Baptiste ^{[3
]}

Cole, Andrew A. ^{[4
]}

Fukui, Akihiko ^{[9
,10
]}

Henderson, Calen B. ^{[11
]}

Ranc, Clement ^{[3
]}

机构：

[1] NASA, Goddard Space Flight Ctr, Code 667, Greenbelt, MD 20771 USA

[2] Univ Maryland, Dept Astron, College Pk, MD 20742 USA

[3] UPMC, CNRS, Inst Astrophys Paris, UMR 7095, 98bis Blvd Arago, F-75014 Paris, France

[4] Univ Tasmania, Sch Phys Sci, Private Bag 37, Hobart, Tas 7001, Australia

[5] Massey Univ, Inst Nat & Math Sci, Auckland 0745, New Zealand

[6] Univ Tokyo, Dept Astron, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan

[7] Natl Astron Observ Japan, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan

[8] Univ Calif Berkeley, Berkeley, CA 94720 USA

[9] Univ Tokyo, Grad Sch Sci, Dept Earth & Planetary Sci, Bunkyo Ku, 7-3-1 Hongo, Tokyo 1130033, Japan

[10] Inst Astrofis Canarias, Via Lactea S-N, E-38205 Tenerife, Spain

[11] CALTECH, IPAC, NASA, Exoplanet Sci Inst, Pasadena, CA 91125 USA

来源：

ASTRONOMICAL JOURNAL | 2021年 / 162卷 / 02期

基金：

澳大利亚研究理事会;

关键词：

GAS-GIANT PLANET; MICROLENSING EVENT; LUMINOSITY-RELATION; COLD NEPTUNE; STARS; ANALOG; EARTH; DISCOVERY; PARALLAX; VELOCITY;

D O I：

10.3847/1538-3881/abfec5

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We present Keck/NIRC2 adaptive optics imaging of planetary microlensing event MOA-2007-BLG-400 that resolves the lens star system from the source. We find that the MOA-2007-BLG-400L planetary system consists of a 1.71 +/- 0.27M (Jup) planet orbiting a 0.69 +/- 0.04M (circle dot) K-dwarf host star at a distance of 6.89 +/- 0.77 kpc from the Sun. So, this planetary system probably resides in the Galactic bulge. The planet-host star projected separation is only weakly constrained due to the close-wide light-curve degeneracy; the 2 sigma projected separation ranges are 0.6-1.0 au and 4.7-7.7 au for close and wide solutions, respectively. This host mass is at the top end of the range of masses predicted by a standard Bayesian analysis. Our Keck follow-up program has now measured lens-source separations for six planetary microlensing events, and five of these six events have host star masses above the median prediction under the assumption that assumes that all stars have an equal chance of hosting planets detectable by microlensing. This suggests that more massive stars may be more likely to host planets of a fixed mass ratio that orbit near or beyond the snow line. These results also indicate the importance of host star mass measurements for exoplanets found by microlensing. The microlensing survey imaging data from NASA's Nancy Grace Roman Space Telescope (formerly WFIRST) mission will be doing mass measurements like this for a huge number of planetary events.

引用

页数：13