New Giant Planet beyond the Snow Line for an Extended MOA Exoplanet Microlens Sample [EPA]

http://arxiv.org/abs/2107.03400


Characterizing a planet detected by microlensing is hard if the planetary signal is weak or the lens-source relative trajectory is far from caustics. However, statistical analyses of planet demography must include those planets to accurately determine occurrence rates. As part of a systematic modeling effort in the context of a $>10$-year retrospective analysis of MOA’s survey observations to build an extended MOA statistical sample, we analyze the light curve of the planetary microlensing event MOA-2014-BLG-472. This event provides weak constraints on the physical parameters of the lens, as a result of a planetary anomaly occurring at low magnification in the light curve. We use a Bayesian analysis to estimate the properties of the planet, based on a refined Galactic model and the assumption that all Milky Way’s stars have an equal planet-hosting probability. We find that a lens consisting of a $1.9^{+2.2}{-1.2}\,\mathrm{M}\mathrm{J}$ giant planet orbiting a $0.31^{+0.36}{-0.19}\,\mathrm{M}\odot$ host at a projected separation of $0.75\pm0.24\,\mathrm{au}$ is consistent with the observations and is most likely, based on the Galactic priors. The lens most probably lies in the Galactic bulge, at $7.2^{+0.6}_{-1.7}\mathrm{kpc}$ from Earth. The accurate measurement of the measured planet-to-host star mass ratio will be included in the next statistical analysis of cold planet demography detected by microlensing.

Read this paper on arXiv…

C. Ranc, D. Bennett, R. Barry, et. al.
Fri, 9 Jul 21
57/62

Comments: accepted for publication in the Monthly Notices of the Royal Astronomical Society, 19 pages, 7 figures, 2 tables