Moa 2003-blg-37: a Bulge Jerk-parallax Microlens Degeneracy
نویسندگان
چکیده
We analyze the Galactic bulge microlensing event MOA 2003-BLG-37. Although the Einstein timescale is relatively short, tE 1⁄4 43 days, the light curve displays deviations consistent with parallax effects due to the Earth’s accelerated motion. We show that the 2 surface has four distinct local minima that are induced by the ‘‘jerk-parallax’’ degeneracy, with pairs of solutions having projected Einstein radii r̃E 1⁄4 1:76 and 1.28 AU, respectively. This is the second event displaying such a degeneracy and the first toward the Galactic bulge. For both events, the jerk-parallax formalism accurately describes the offsets between the different solutions, giving hope that when extra solutions exist in future events they can easily be found. However, the morphologies of the 2 surfaces for the two events are quite different, implying that much remains to be understood about this degeneracy. Subject headings: Galaxy: bulge — gravitational lensing
منابع مشابه
ar X iv : a st ro - p h / 04 01 25 0 v 1 1 3 Ja n 20 04 MOA 2003 - BLG - 37 : A Bulge Jerk - Parallax Microlens Degeneracy
– 2 – We analyze the Galactic bulge microlensing event MOA 2003-BLG-37. Although the Einstein timescale is relatively short, t E = 43 days, the lightcurve displays deviations consistent with parallax effects due to the Earth's accelerated motion. We show that the χ 2 surface has four distinct local minima that are induced by the " jerk-parallax " degeneracy, with pairs of solutions having proje...
متن کاملar X iv : a st ro - p h / 04 01 25 0 v 2 14 M ar 2 00 4 MOA 2003 - BLG - 37 : A Bulge Jerk - Parallax Microlens Degeneracy
– 2 – We analyze the Galactic bulge microlensing event MOA 2003-BLG-37. Although the Einstein timescale is relatively short, t E = 43 days, the lightcurve displays deviations consistent with parallax effects due to the Earth's accelerated motion. We show that the χ 2 surface has four distinct local minima that are induced by the " jerk-parallax " degeneracy, with pairs of solutions having proje...
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