Astrophysical: Gravitational microlensing

  • Publication
    Constraints on the Abundance of Primordial Black Holes from X-Ray Quasar Microlensing Observations: Substellar to Planetary Mass Range

    We use X-ray observations of quasar microlensing (sensitive to smaller compact objects than in the optical) to study the possible presence of a population of...

  • Publication
    Free-floating Planet Mass Function from MOA-II 9 yr Survey toward the Galactic Bulge

    We present the first measurement of the mass function of free-floating planets (FFPs), or very wide orbit planets down to an Earth mass, from the MOA-II...

  • Publication
    Influence of Microlensing on the Active Galactic Nucleus Fe Kalpha Line

    We have studied the influence of gravitational microlensing on the Fe Kalpha line originating from a compact accretion disc of active galactic nuclei. We found...

  • Publication
    KMT-2019-BLG-0842Lb: A Cold Planet below the Uranus/Sun Mass Ratio

    We report the discovery of a cold planet with a very low planet/host mass ratio of q = (4.09 ± 0.27) × 10-5, which is similar to the ratio of Uranus/Sun (q = 4...

  • Publication
    Kojima-1Lb Is a Mildly Cold Neptune around the Brightest Microlensing Host Star

    We report the analysis of additional multiband photometry and spectroscopy and new adaptive optics (AO) imaging of the nearby planetary microlensing event TCP...

  • Publication
    MOA-2007-BLG-400 A Super-Jupiter-mass Planet Orbiting a Galactic Bulge K-dwarf Revealed by Keck Adaptive Optics Imaging

    We present Keck/NIRC2 adaptive optics imaging of planetary microlensing event MOA-2007-BLG-400 that resolves the lens star system from the source. We find that...

  • Publication
    MOA-2020-BLG-135Lb: A New Neptune-class Planet for the Extended MOA-II Exoplanet Microlens Statistical Analysis

    We report the light-curve analysis for the event MOA-2020-BLG-135, which leads to the discovery of a new Neptune-class planet, MOA-2020-BLG-135Lb. With a...

  • Publication
    MOA-2020-BLG-208Lb: Cool Sub-Saturn-mass Planet within Predicted Desert

    We analyze the MOA-2020-BLG-208 gravitational microlensing event and present the discovery and characterization of a new planet, MOA-2020-BLG-208Lb, with an...

  • Publication
    MOA-bin-29b: A Microlensing Gas-giant Planet Orbiting a Low-mass Host Star

    We report the discovery of a gas-giant planet orbiting a low-mass host star in the microlensing event MOA-bin-29 that occurred in 2006. We find five degenerate...