Two new free-floating or wide-orbit planets from microlensing

@article{Mrz2019TwoNF,
title={Two new free-floating or wide-orbit planets from microlensing},
author={Przemek Mr{\'o}z and Andrzej Udalski and David P. Bennett and Yoon-Hyun Ryu and Takahiro Sumi and Yossi Shvartzvald and Jan Skowron and R. Poleski and Paweł Pietrukowicz and S. Kozłowski and Michał K. Szymański and Lukasz Wyrzykowski and Igor Soszyński and Krzysztof Ulaczyk and Krzysztof Rybicki and Patryk Iwanek and Michael D. Albrow and S.-J. Chung and A. Gould and C. Han and Kyu-Ha Hwang and Y. K. Jung and In-Gu Shin and Jennifer C. Yee and W.Zang and S. M. Cha and D-J. Kim and H.-W. Kim and S.-L. Kim and C.-U. Lee and D.J. Lee and Y. Lee and B.-G. Park and Richard W. Pogge and Fumio Abe and Richard K. Barry and Aparna Bhattacharya and Ian A.Bond and Martin A Donachie and Akihiko Fukui and Yuki Hirao and Yoshitaka Itow and Kohei Kawasaki and Iona Kondo and Naoki Koshimoto and M. C. A. Li and Yutaka Matsubara and Yasushi Muraki and Shota Miyazaki and Masayuki Nagakane and Cl{\'e}ment Ranc and Nicholas J. Rattenbury and Haruno Suematsu and Denis J. Sullivan and Daisuke Suzuki and Paul J. Tristram and Atsunori Yonehara and Dan Maoz and Shai Kaspi and Matan Friedmann},
journal={Astronomy \& Astrophysics},
year={2019}
}
Planet formation theories predict the existence of free-floating planets that have been ejected from their parent systems. Although they emit little or no light, they can be detected during gravitational microlensing events. Microlensing events caused by rogue planets are characterized by very short timescales tE (typically below two days) and small angular Einstein radii θE (up to several μas). Here we present the discovery and characterization of two ultra-short microlensing events identified… Expand
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