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OGLE-2018-BLG-0567Lb and OGLE-2018-BLG-0962Lb: Two Microlensing Planets through Planetary-Caustic Channel

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 نشر من قبل Youn Kil Jung
 تاريخ النشر 2021
  مجال البحث فيزياء
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We present the analyses of two microlensing events, OGLE-2018-BLG-0567 and OGLE-2018-BLG-0962. In both events, the short-lasting anomalies were densely and continuously covered by two high-cadence surveys. The light-curve modeling indicates that the anomalies are generated by source crossings over the planetary caustics induced by planetary companions to the hosts. The estimated planet/host separation (scaled to the angular Einstein radius $theta_{rm E}$) and mass ratio are $(s, q) = (1.81, 1.24times10^{-3})$ and $(s, q) = (1.25, 2.38times10^{-3})$, respectively. From Bayesian analyses, we estimate the host and planet masses as $(M_{rm h}, M_{rm p}) = (0.24_{-0.13}^{+0.16},M_{odot}, 0.32_{-0.16}^{+0.34},M_{rm J})$ and $(M_{rm h}, M_{rm p}) = (0.55_{-0.29}^{+0.32},M_{odot}, 1.37_{-0.72}^{+0.80},M_{rm J})$, respectively. These planetary systems are located at a distance of $7.07_{-1.15}^{+0.93},{rm kpc}$ for OGLE-2018-BLG-0567 and $6.47_{-1.73}^{+1.04},{rm kpc}$ for OGLE-2018-BLG-0962, suggesting that they are likely to be near the Galactic bulge. The two events prove the capability of current high-cadence surveys for finding planets through the planetary-caustic channel. We find that most published planetary-caustic planets are found in Hollywood events in which the source size strongly contributes to the anomaly cross section relative to the size of the caustic.



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