KMT-2019-BLG-2073: Fourth Free-floating Planet Candidate with θ E < 10 μas

@article{Kim2021KMT2019BLG2073FF,
  title={KMT-2019-BLG-2073: Fourth Free-floating Planet Candidate with $\theta$ E < 10 $\mu$as},
  author={Hyoun-Woo Kim and Kyu-Ha Hwang and A. Gould and Jennifer C. Yee and Yoon-Hyun Ryu and Michael D. Albrow and Sun-Ju Chung and Cheongho Han and Youn Kil Jung and Chung-Uk Lee and In-Gu Shin and Yossi Shvartzvald and Weicheng Zang and Sang-Mok Cha and Dong-Jin Kim and Seung-Lee Kim and Dong-Joo Lee and Yongseok Lee and Byeong-Gon Park and Richard W. Pogge},
  journal={The Astronomical Journal},
  year={2021},
  volume={162}
}
We analyze the very short Einstein timescale (t E ≃ 7 hr) event KMT-2019-BLG-2073. Making use of the pronounced finite-source effects generated by the clump giant source, we measure the Einstein radius θ E ≃ 4.8 μas and so infer a mass M=59M⊕(πrel/16μas)−1 , where π rel is the lens-source relative parallax. We find no significant evidence for a host of this planetary-mass object, though one could be present at sufficiently wide separation. If so, it would be detectable after about 10 yr. This… 
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