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تسجيل مستخدم جديدOGLE-2018-BLG-1428Lb: a Jupiter-mass planet beyond the snow line of a dwarf star
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We present the analysis of the microlensing event OGLE-2018-BLG-1428, which has a short-duration ($sim 1$ day) caustic-crossing anomaly. The event was caused by a planetary lens system with planet/host mass ratio $q=1.7times10^{-3}$. Thanks to the detection of the caustic-crossing anomaly, the finite source effect was well measured, but the microlens parallax was not constrained due to the relatively short timescale ($t_{rm E}=24$ days). From a Bayesian analysis, we find that the host star is a dwarf star $M_{rm host}=0.43^{+0.33}_{-0.22} M_{odot}$ at a distance $D_{rm L}=6.22^{+1.03}_{-1.51} {rm kpc}$ and the planet is a Jovian-mass planet $M_{rm p}=0.77^{+0.77}_{-0.53} M_{rm J}$ with a projected separation $a_{perp}=3.30^{+0.59}_{-0.83} {rm au}$. The planet orbits beyond the snow line of the host star. Considering the relative lens-source proper motion of $mu_{rm rel} = 5.58 pm 0.38 rm mas yr^{-1}$, the lens can be resolved by adaptive optics with a 30m telescope in the future.
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