MOA-2006-BLG-074: Recognizing Xallarap Contaminants in Planetary Microlensing

Rota, P.; Hirao, Y.; Bozza, V.; Abe, F.; Barry, R.; Bennett, D. P.; Bhattacharya, A.; Bond, I. A.; Donachie, M.; Fukui, A.; Fujii, H.; Silva, S. Ishitani; Itow, Y.; Kirikawa, R.; Koshimoto, N.; Li, M. C. A.; Matsubara, Y.; Miyazaki, S.; Muraki, Y.; Olmschenk, G.; Ranc, C.; Satoh, Y.; Sumi, T.; Suzuki, D.; Tristram, P. J.; Yonehara, A.
Bibliographical reference

The Astronomical Journal

Advertised on:
8
2021
Number of authors
26
IAC number of authors
1
Citations
6
Refereed citations
5
Description
MOA-2006-BLG-074 was selected as one of the most promising planetary candidates in a retrospective analysis of the MOA collaboration: its asymmetric high-magnification peak can be perfectly explained by a source passing across a central caustic deformed by a small planet. However, after a detailed analysis of the residuals, we have realized that a single lens and a source orbiting with a faint companion provides a more satisfactory explanation for all the observed deviations from a Paczynski curve and the only physically acceptable interpretation. Indeed the orbital motion of the source is constrained enough to allow a very good characterization of the binary source from the microlensing light curve. The case of MOA-2006-BLG-074 suggests that the so-called xallarap effect must be taken seriously in any attempts to obtain accurate planetary demographics from microlensing surveys.