• Received : 2016.02.27
  • Accepted : 2016.04.27
  • Published : 2016.06.30


We report the characterization of a massive (mp = 3.9±1.4Mjup) microlensing planet (OGLE-2015-BLG-0954Lb) orbiting an M dwarf host (M = 0.33 ± 0.12M) at a distance toward the Galactic bulge of $0.6^{+0.4}_{-0.2}kpc$, which is extremely nearby by microlensing standards. The planet-host projected separation is a⊥ ~ 1.2AU. The characterization was made possible by the wide-field (4 deg2) high cadence (Γ = 6 hr–1) monitoring of the Korea Microlensing Telescope Network (KMTNet), which had two of its three telescopes in commissioning operations at the time of the planetary anomaly. The source crossing time t* = 16 min is among the shortest ever published. The high-cadence, wide-field observations that are the hallmark of KMTNet are the only way to routinely capture such short crossings. High-cadence resolution of short caustic crossings will preferentially lead to mass and distance measurements for the lens. This is because the short crossing time typically implies a nearby lens, which enables the measurement of additional effects (bright lens and/or microlens parallax). When combined with the measured crossing time, these effects can yield planet/host masses and distance.


gravitational microlensing;planets


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  4. OGLE-2013-BLG-1761Lb: A Massive Planet around an M/K Dwarf vol.154, pp.1, 2017,
  5. OGLE-2016-BLG-1003: First Resolved Caustic-crossing Binary-source Event Discovered by Second-generation Microlensing Surveys vol.841, pp.2, 2017,
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Grant : 우주감시기술개발

Supported by : 한국천문연구원