An Extreme Magnification Event with a Strong Sensitivity to Planets OGLE-2008-BLG-279 An Extreme Magnification Event with a Strong Sensitivity to Planets Jennifer Yee Collaborators: Andy Gould, Subo Dong, Scott Gaudi, Szymon Kozłowski, μFUN, OGLE, MOA, PLANET

Point-Source Point-Lens X f(u0)‏ tE X t0 Ml, Dl → mp, b(AU)‏

Additional Parameters from EMEs Finite Source: ρ* θE = θ*/ρ* Terrestrial Parallax: πE 1/Dl = πs + θEπE Ml = θE/(κπE)‏

Well-Measured Finite Source Effects Impact Parameter Impact Parameter/Source Size Impact Parameter

Measured Parameters t0 = 4617.34784 ± 0.00007 days tE = 110. ± 9 days ρ* = 0.00066 ± 0.00006 θE = θ*/ρ* = 0.90 ± 0.09 mas → rE = 3.3 ± 0.3 AU Ml = θE/(κπE) = 0.69 ± 0.15 Mסּ Dl = 3.7 ± 0.8 kpc

CMD

Identifying the Blend V-I

Shear

Trajectory Han (2009) ApJ, 691L

Shear

Planet Sensitivity

Planet Sensitivity

Planet Sensitivity

Planet Sensitivity

Detection Efficiency 99% 25%

Conclusions Measured Finite Source Effects Measured Terrestrial Parallax Ml = 0.69 Mסּ, Dl = 3.7 kpc Sensitivity to planets mp> 2 MMars Rule out planets mp = 1 MJup, b=[0.6,19.5] AU