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arXiv · 2207.05874

VLT, GROND and Danish Telescope observations of transits in the TRAPPIST-1 system

John Southworth·L. Mancini·M. Dominik·U. G. Jørgensen·V. Bozza·M. J. Burgdorf·R. Figuera Jaimes·L. K. Haikala·Th. Henning·T. C. Hinse·M. Hundertmark·P. Longa-Peña·M. Rabus·S. Rahvar·S. Sajadian·J. Skottfelt·C. Snodgrass
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Abstract

TRAPPIST-1 is an ultra-cool dwarf that hosts seven known transiting planets. We present photometry of the system obtained using three telescopes at ESO La Silla (the Danish 1.54-m telescope and the 2.2-m MPI telescope) and Paranal (Unit Telescope 1 of the Very Large Telescope). We obtained 18 light curves from the Danish telescope, eight from the 2.2-m and four from the VLT. From these we measure 25 times of mid-transit for four of the planets (b, c, f, g). These light curves and times of mid-transit will be useful in determining the masses and radii of the planets, which show variations in their transit times due to gravitational interactions.

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John Southworth, L. Mancini, M. Dominik, U. G. Jørgensen, V. Bozza, M. J. Burgdorf, R. Figuera Jaimes, L. K. Haikala, Th. Henning, T. C. Hinse, M. Hundertmark, P. Longa-Peña, M. Rabus, S. Rahvar, S. Sajadian, J. Skottfelt, C. Snodgrass. 2022-07-12. VLT, GROND and Danish Telescope observations of transits in the TRAPPIST-1 system. https://arxiv.org/abs/2207.05874

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