Extreme Magnification Microlensing Event OGLE-2008-BLG-279: Strong Limits on Planetary Companions to the Lens Star

J. C. Yee , A. Udalski , T. Sumi , Subo Dong , S. Kozłowski , J. C. Bird , A. Cole , D. Higgins , J. Mccormick , L. A. G. Monard , D. Polishook , A. Shporer , O. Spector , M. K. Szymański , M. Kubiak , G. Pietrzyński , I. Soszyński , O. Szewczyk , K. Ulaczyk , Ł. Wyrzykowski , R. Poleski , W. Allen , M. Bos , G. W. Christie , D. L. Depoy , J. D. Eastman , B. S. Gaudi , A. Gould (1) , C. Han , S. Kaspi , C.-U. Lee , F. Mallia , A. Maury , D. Maoz , T. Natusch , B.-G. Park , R. W. Pogge , R. Santallo , F. Abe , I. A. Bond , A. Fukui , K. Furusawa , J. B. Hearnshaw , S. Hosaka , Y. Itow , K. Kamiya , A. V. Korpela , P. M. Kilmartin , W. Lin , C. H. Ling , S. Makita , K. Masuda , Y. Matsubara , N. Miyake , Y. Muraki , M. Nagaya , K. Nishimoto , K. Ohnishi , Y. C. Perrott , N. J. Rattenbury , T. Sako , To. Saito , L. Skuljan , D. J. Sullivan , W. L. Sweatman , P. J. Tristram , P. C. M. Yock , M. D. Albrow , V. Batista , P. Fouqué (2) , J.-P. Beaulieu , D. P. Bennett , A. Cassan , J. Comparat , C. Coutures (3) , S. Dieters , J. Greenhill , K. Horne , N. Kains , D. Kubas , Roland Martin , J. Menzies , J. Wambsganss (4) , A. Williams , M. Zub

1 Ohio State University - Department of Astronomy
2 LATT - Laboratoire Astrophysique de Toulouse-Tarbes
3 IAP - Institut d'Astrophysique de Paris
4 ARI - Astronomische Rechen-Institut [Heidelberg]

We analyze the extreme high-magnification microlensing event OGLE-2008-BLG-279, which peaked at a maximum magnification of A ~ 1600 on 2008 May 30. The peak of this event exhibits both finite-source effects and terrestrial parallax, from which we determine the mass of the lens, Ml = 0.64 ± 0.10 M sun, and its distance, Dl = 4.0 ± 0.6 kpc. We rule out Jupiter-mass planetary companions to the lens star for projected separations in the range 0.5-20 AU. More generally, we find that this event was sensitive to planets with masses as small as 0.2 \;M_\oplus \simeq 2 \;M_{Mars} with projected separations near the Einstein ring (~3 AU).

Mots clés: gravitational lensing; planetary systems; planetary systems: formation

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]; Planétologie et astrophysique de la terre [astro-ph.EP]

J. C. Yee, A. Udalski, T. Sumi, Subo Dong, S. Kozłowski, et al.. Extreme Magnification Microlensing Event OGLE-2008-BLG-279: Strong Limits on Planetary Companions to the Lens Star. The Astrophysical Journal, 2009, 703, pp.2082-2090. ⟨10.1088/0004-637X/703/2/2082⟩. ⟨hal-00418877⟩