Gaia22dkvLb: A Microlensing Planet Potentially Accessible to Radial-Velocity Characterization
Abstract
We report discovering an exoplanet from following up a microlensing event alerted by Gaia. The event Gaia22dkv is toward a disk source rather than the traditional bulge microlensing fields. Our primary analysis yields a Jovian planet with M_p = 0.59^{+0.15}_{-0.05} M_J at a projected orbital separation r_perp = 1.4^{+0.8}_{-0.3} AU, and the host is a ~1.1 M_sun turnoff star at ~1.3 kpc. At r'~14, the host is far brighter than any previously discovered microlensing planet host, opening up the opportunity of testing the microlensing model with radial velocity (RV) observations. RV data can be used to measure the planet's orbital period and eccentricity, and they also enable searching for inner planets of the microlensing cold Jupiter, as expected from the ''inner-outer correlation'' inferred from Kepler and RV discoveries. Furthermore, we show that Gaia astrometric microlensing will not only allow precise measurements of its angular Einstein radius theta_E, but also directly measure the microlens parallax vector and unambiguously break a geometric light-curve degeneracy, leading to definitive characterization of the lens system.
Keywords
Cite
@article{arxiv.2309.03944,
title = {Gaia22dkvLb: A Microlensing Planet Potentially Accessible to Radial-Velocity Characterization},
author = {Zexuan Wu and Subo Dong and Tuan Yi and Zhuokai Liu and Kareem El-Badry and Andrew Gould and L. Wyrzykowski and K. A. Rybicki and Etienne Bachelet and Grant W. Christie and L. de Almeida and L. A. G. Monard and J. McCormick and Tim Natusch and P. Zielinski and Huiling Chen and Yang Huang and Chang Liu and A. Merand and Przemek Mroz and Jinyi Shangguan and Andrzej Udalski and J. Woillez and Huawei Zhang and Franz-Josef Hambsch and P. J. Mikolajczyk and M. Gromadzki and M. Ratajczak and Katarzyna Kruszynska and N. Ihanec and Uliana Pylypenko and M. Sitek and K. Howil and Staszek Zola and Olga Michniewicz and Michal Zejmo and Fraser Lewis and Mateusz Bronikowski and Stephen Potter and Jan Andrzejewski and Jaroslav Merc and Rachel Street and Akihiko Fukui and R. Figuera Jaimes and V. Bozza and P. Rota and A. Cassan and M. Dominik and Y. Tsapras and M. Hundertmark and J. Wambsganss and K. Bakowska and A. Slowikowska},
journal= {arXiv preprint arXiv:2309.03944},
year = {2024}
}
Comments
Accepted by AJ