hide
Free keywords:
gravitational lensing: micro
planets and satellites: detection
stars: individual: KMT-2016-BLG-1397
Astrophysics - Earth and Planetary
Astrophysics
Abstract:
We report the discovery of a giant planet in the KMT-2016-BLG-1397 microlensing event, which was found by The Korea Microlensing Telescope Network alone. The timescale of this event is t E = 40.0 ± 0.5 days, and the mass ratio between the lens star and its companion is q = 0.016 ± 0.002. The planetary perturbation in the light curve is a smooth bump, resulting in the classical binary-lens/binary-source (2L1S/1L2S) degeneracy. We measure the V - I color of the (putative) two sources in the 1L2S model, and then effectively rule out the binary- source solution. The finite-source effect is marginally detected. Combined with the limits on the blend flux and the probability distribution of the source size normalized by the Einstein radius ρ, a Bayesian analysis yields the lens mass {M}{{L}}={0.45}-0.28+0.33 {M}☉ , at distance of {D}{{L}}={6.60}-1.30+1.10 kpc. Thus, the companion is a super-Jupiter of a mass {m}p={7.0}-4.3+5.2 {M}J, at a projected separation {r}\perp ={5.1}-1.7+1.5 au, indicating that the planet is well beyond the snow line of the host star.
