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

TL;DR

This study presents precise transit timing measurements of TRAPPIST-1 b and c using APO telescope data, aiming to refine their mass estimates through transit timing variations and proposing an analysis procedure for late-M star transits.

Contribution

It provides new transit times for TRAPPIST-1 b and c and outlines a methodology for analyzing transits of late-M stars with APO.

Findings

Transit times for TRAPPIST-1 b and c are precisely measured.

Results will help constrain the planetary masses.

A procedure for analyzing late-M star transits is outlined.

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.