A Terrestrial-mass Rogue Planet Candidate Detected in the Shortest-timescale Microlensing Event

  title={A Terrestrial-mass Rogue Planet Candidate Detected in the Shortest-timescale Microlensing Event},
  author={Przemek Mr{\'o}z and Radosław Poleski and A. Gould and Andrzej Udalski and Takahiro Sumi and Michał K. Szymański and Igor Soszyński and Paweł Pietrukowicz and Szymon Kozłowski and Jan Skowron and Krzysztof Ulaczyk and Michael D. Albrow and Sun-Ju Chung and Cheongho Han and Kyu-Ha Hwang and Youn Kil Jung and Hyoun-Woo Kim and Yoon-Hyun Ryu and In-Gu Shin and Yossi Shvartzvald and Jennifer C. Yee and Weicheng Zang and Sang-Mok Cha and Dong-Jin Kim and Seung-Lee Kim and Chung-Uk Lee and Dong-Joo Lee and Yongseok Lee and B.-G. Park and Richard W. Pogge},
  journal={The Astrophysical Journal Letters},
Some low-mass planets are expected to be ejected from their parent planetary systems during early stages of planetary system formation. According to planet formation theories, such as the core accretion theory, typical masses of ejected planets should be between 0.3 and 1.0 M ⊕. Although in practice such objects do not emit any light, they may be detected using gravitational microlensing via their light-bending gravity. Microlensing events due to terrestrial-mass rogue planets are expected to… 

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