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MOA Data Reveal a New Mass, Distance, and Relative Proper Motion for Planetary System OGLE-2015-BLG-0954L

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 نشر من قبل David Bennett
 تاريخ النشر 2017
  مجال البحث فيزياء
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We present the MOA Collaboration light curve data for planetary microlensing event OGLE-2015-BLG-0954, which was previously announced in a paper by the KMTNet and OGLE Collaborations. The MOA data cover the caustic exit, which was not covered by the KMTNet or OGLE data, and they provide a more reliable measurement of the finite source effect. The MOA data also provide a new source color measurement that reveals a lens-source relative proper motion of $mu_{rm rel} = 11.8pm 0.8,$mas/yr, which compares to the value of $mu_{rm rel} = 18.4pm 1.7,$mas/yr reported in the KMTNet-OGLE paper. This new MOA value for $mu_{rm rel}$ has an a priori probability that is a factor of $sim 100$ times larger than the previous value, and it does not require a lens system distance of $D_L < 1,$kpc. Based on the corrected source color, we find that the lens system consists of a planet of mass $3.4^{+3.7}_{-1.6} M_{rm Jup}$ orbiting a $0.30^{+0.34}_{-0.14}M_odot$ star at an orbital separation of $2.1^{+2.2}_{-1.0},$AU and a distance of $1.2^{+1.1}_{-0.5},$kpc.



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