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arXiv · 1801.04460

Photometric Analysis and Transit Times of TRAPPIST-1 b and c

Brett M. Morris·Eric Agol·Suzanne L. Hawley
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Abstract

TRAPPIST-1 hosts seven Earth-sized planets transiting an M8 star. We observed mid-transit times of each of the inner two planets with the Astrophysical Research Consortium (ARC) 3.5 m Telescope at Apache Point Observatory (APO) to help constrain the planet masses with transit timing variations, and we outline a procedure for analyzing transit observations of late-M stars with APO. The transit times of TRAPPIST-1 b and c are $\mathrm{BJD}_{\mathrm{TDB}} = 2457580.87634^{+0.00034}_{-0.00034}$ and $2457558.89477^{+0.00080}_{-0.00085}$, respectively, which will help constrain the planet masses.

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Brett M. Morris, Eric Agol, Suzanne L. Hawley. 2018-01-13. Photometric Analysis and Transit Times of TRAPPIST-1 b and c. https://arxiv.org/abs/1801.04460

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