Analysis of Planetary Microlensing Event OGLE-2014-BLG-0221, with a Jupiter Mass Ratio Planet Orbiting a Late-Type Star, or Possibly a Stellar Remnant

Rintaro Kirikawa  ✧  Osaka University, Japan

We present the analysis of microlensing event OGLE-2014-BLG-0221, which was observed by both the MOA and OGLE Collaborations. Our light curve modeling reveals two degenerate models, one with a small microlensing parallax signal constrained only by an upper limit, and one with a large parallax signal of \(\pi_\mathrm{E}\sim0.4\). The two models are similar in their planetary parameters with a mass ratio of \(q\sim10^{-3}\) and a separation of \(s\sim1.1\). The small parallax model implies that the lens system consists of a late-type star orbited by a gas giant, the large parallax model favors a nearby massive lens. Limits on the excess flux at the position of the source suggest a dark lens. If the dark lens model is true, this would be the second planet found around a stellar remnant. Since the models predict different relative proper motion and source and blending fluxes, future high angular resolution follow-up observations would be able to rule out either of the models and reveal true characteristic of the lens system.