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تسجيل مستخدم جديدOGLE-2017-BLG-1049: Another giant planet microlensing event
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We report a giant exoplanet discovery in the microlensing event OGLE-2017-BLG-1049, which is a planet-host star mass ratio of $q=9.53pm0.39times10^{-3}$ and has a caustic crossing feature in the Korea Microlensing Telescope Network (KMTNet) observations. The caustic crossing feature yields an angular Einstein radius of $theta_{rm E}=0.52 pm 0.11 {rm mas}$. However, the microlens parallax is not measured because of the time scale of the event $t_{rm E}simeq 29 {rm days}$, which is not long enough in this case to determine the microlens parallax. Thus, we perform a Bayesian analysis to estimate physical quantities of the lens system. From this, we find that the lens system has a star with mass $M_{rm h}=0.55^{+0.36}_{-0.29} M_{odot}$ hosting a giant planet with $M_{rm p}=5.53^{+3.62}_{-2.87} M_{rm Jup}$, at a distance of $D_{rm L}=5.67^{+1.11}_{-1.52} {rm kpc}$. The projected star-planet separation in units of the Einstein radius $(theta_{rm E})$ corresponding to the total mass of the lens system is $a_{perp}=3.92^{+1.10}_{-1.32} rm{au}$. This means that the planet is located beyond the snow line of the host. The relative lens-source proper motion is $mu_{rm rel}sim 7 rm{mas yr^{-1}}$, thus the lens and source will be separated from each other within 10 years. Then the flux of the host star can be measured by a 30m class telescope with high-resolution imaging in the future, and thus its mass can be determined.
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