Shortest Microlensing Event with a Bound Planet: KMT-2016-BLG-2605

With a planet–host mass ratio q = 0.012 ± 0.001, KMT-2016-BLG-2605 has the shortest Einstein timescale, t E = 3.41 ± 0.13 days, of any planetary microlensing event to date. This prompts us to examine the full sample of seven short ( t E < 7 days) planetary events with good q measurements. We find...

Full description

Saved in:
Bibliographic Details
Published in:The Astronomical journal 2021-09, Vol.162 (3), p.96
Main Authors: Ryu, Yoon-Hyun, Hwang, Kyu-Ha, Gould, Andrew, Yee, Jennifer C., Albrow, Michael D., Chung, Sun-Ju, Han, Cheongho, Jung, Youn Kil, Kim, Hyoun-Woo, Shin, In-Gu, Shvartzvald, Yossi, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W.
Format: Article
Language:English
Subjects:
Accretion disks
Adaptive optics
Astronomy
ASTROPHYSICS, COSMOLOGY AND ASTRONOMY
ATOMIC AND MOLECULAR PHYSICS
DEUTERIUM
Galactic bulge
Gravitational microlensing
Gravitational microlensing exoplanet detection
Hydrogen
HYDROGEN BURNING
Light curve
Microlenses
MORPHOLOGY
OPTICS
Planet formation
PLANETS
PROPER MOTION
STARS
TELESCOPES
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:With a planet–host mass ratio q = 0.012 ± 0.001, KMT-2016-BLG-2605 has the shortest Einstein timescale, t E = 3.41 ± 0.13 days, of any planetary microlensing event to date. This prompts us to examine the full sample of seven short ( t E < 7 days) planetary events with good q measurements. We find that six have clustered Einstein radii θ E = 115 ± 20 μ as and lens–source relative proper motions μ rel ≃ 9.5 ± 2.5 mas yr −1 . For the seventh, these two quantities could not be measured. These distributions are consistent with a Galactic bulge population of very low mass (VLM) hosts near the hydrogen-burning limit. This conjecture could be verified by imaging at first adaptive optics light on next-generation (30 m) telescopes. Based on a preliminary assessment of the sample, “planetary” companions (i.e., below the deuterium-burning limit) are divided into “genuine planets,” formed in their disks by core accretion, and VLM brown dwarfs, which form like stars. We discuss techniques for expanding the sample, which include taking account of the peculiar “anomaly-dominated” morphology of the KMT-2016-BLG-2605 light curve.
ISSN:0004-6256
1538-3881
1538-3881
DOI:10.3847/1538-3881/ac062a