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We present the analysis of a planetary microlensing event OGLE-2019-BLG-0362 with a short-duration anomaly (~0.4 days) near the peak of the light curve, which is caused by the resonant caustic. The event has a severe degeneracy with Δχ^{2} = 0.9 between the close and the wide binary lens models both with planet-host mass ratio q ≃ 0.007. We measure the angular Einstein radius but not the microlens parallax, and thus we perform a Bayesian analysis to estimate the physical parameters of the lens. We find that the OGLE-2019-BLG-0362L system is a super-Jovian-mass planet M_{p}=3.26^{+0.83}_{-0.58} M_{J} orbiting an M dwarf M_{h} = 0.42^{+0.34}_{-0.23} M_{⊙} at a distance D_{L} = 5.83^{+1.04}_{-1.55} kpc. The projected star-planet separation is a_{⊥} = 2.18^{+0.58}_{-0.72} AU, which indicates that the planet lies beyond the snow line of the host star.
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OGLE-2018-BLG-0799Lb: a q ∼ 2.7 × 10−3 planet with Spitzer parallax
ABSTRACT We report the discovery and analysis of a planet in the microlensing event OGLE-2018-BLG-0799. The planetary signal was observed by several ground-based telescopes, and the planet-host mass ratio is q = (2.65 ± 0.16) × 10−3. The ground-based observations yield a constraint on the angular Einstein radius θE, and the microlensing parallax vector $$\boldsymbol{{\pi} }_{\rm E}$$, is strongly constrained by the Spitzer data. However, the 2019 Spitzer baseline data reveal systematics in the Spitzer photometry, so there is ambiguity in the magnitude of the parallax. In our preferred interpretation, a full Bayesian analysis using a Galactic model indicates that the planetary system is composed of an $$M_{\rm planet} = 0.26_{-0.11}^{+0.22}M_{\rm J}$$ planet orbiting an $$M_{\rm host} = 0.093_{-0.038}^{+0.082}~\mathrm{M}_{\odot }$$, at a distance of $$D_{\rm L} = 3.71_{-1.70}^{+3.24}$$ kpc. An alternate interpretation of the data shifts the localization of the minima along the arc-shaped microlens parallax constraints. This, in turn, yields a more massive host with median mass of $$0.13 {\, \mathrm{M}_{\odot }}$$ at a distance of 6.3 kpc. This analysis demonstrates the robustness of the osculating circles formalism, but shows that further investigation is needed to assess how systematics affect the specific localization of the microlens parallax vector and, consequently, the inferred physical parameters.
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- Award ID(s):
- 2108414
- PAR ID:
- 10429532
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 514
- Issue:
- 4
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 5952 to 5968
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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We present the analysis of a planetary microlensing event OGLE-2019-BLG-0362 with a short-duration anomaly (~0.4 days) near the peak of the light curve, which is caused by the resonant caustic. The event has a severe degeneracy with Δχ^{2} = 0.9 between the close and the wide binary lens models both with planet-host mass ratio q ≃ 0.007. We measure the angular Einstein radius but not the microlens parallax, and thus we perform a Bayesian analysis to estimate the physical parameters of the lens. We find that the OGLE-2019-BLG-0362L system is a super-Jovian-mass planet M_{p}=3.26^{+0.83}_{-0.58} M_{J} orbiting an M dwarf M_{h} = 0.42^{+0.34}_{-0.23} M_{⊙} at a distance D_{L} = 5.83^{+1.04}_{-1.55} kpc. The projected star-planet separation is a_{⊥} = 2.18^{+0.58}_{-0.72} AU, which indicates that the planet lies beyond the snow line of the host star.more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/mnras/stac1631
