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

## TL;DR

This paper refines the properties of the planetary system OGLE-2015-BLG-0954 using MOA data, providing a more accurate relative proper motion and updated estimates of the planet's mass, host star, and system distance.

## Contribution

It presents new MOA light curve data that improve the measurement of the relative proper motion and system parameters for the planetary microlensing event.

## Key findings

- Revised relative proper motion of 11.8 mas/yr with MOA data
- Updated planetary mass estimate of approximately 3.4 Jupiter masses
- Determined the host star mass and system distance with improved accuracy

## Abstract

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 $\mu_{\rm rel} = 11.8\pm 0.8\,$mas/yr, which compares to the value of $\mu_{\rm rel} = 18.4\pm 1.7\,$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.