Probing the atmosphere of a solar-like star by galactic microlensing at high magnification
/ Authors
F. Abe, D. Bennett, I. Bond, J. Calitz, A. Claret, K. Cook, Y. Furuta, A. Gal-yam, J. Glicenstein, J. Hearnshaw
and 23 more authors
P. Hauschildt, D. Kent, P. Kilmartin, Y. Kurata, K. Masuda, D. Maoz, Y. Matsubara, P. Meintjes, M. Moniez, Y. Muraki, S. Noda, E. Ofek, K. Okajima, L. Philpott, N. Rattenbury, S. Rhie, T. Sako, D. Sullivan, T. Sumi, D. Terndrup, P. Tristram, T. Yanagisawa, P. Yock
/ Abstract
We report a measurement of limb darkening of a solar-like star in the very high magnification microlensing event MOA 2002–BLG–33. A 15 hour deviation from the light curve profile expected for a single lens was monitored intensively in V and I passbands by five telescopes spanning the globe. Our modelling of the light curve showed the lens to be a close binary system whose centre-of-mass passed almost directly in front of the source star. The source star was identified as an F8–G2 main sequence turn-off star. The measured stellar profiles agree with current stellar atmosphere theory to within ~4% in two passbands. The effective angular resolution of the measurements is μ as. These are the first limb darkening measurements obtained by microlensing for a Solar-like star.
Journal: Astronomy and Astrophysics