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arXiv · 1606.02962

Transit timing variation and transmission spectroscopy analyses of the hot Neptune GJ3470b

S. Awiphan·E. Kerins·S. Pichadee·S. Komonjinda·V. S. Dhillon·W. Rujopakarn·S. Poshyachinda·T. R. Marsh·D. E. Reichart·K. M. Ivarsen·J. B. Haislip
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Abstract

GJ3470b is a hot Neptune exoplanet orbiting an M dwarf and the first sub-Jovian planet to exhibit Rayleigh scattering. We present transit timing variation (TTV) and transmission spectroscopy analyses of multi-wavelength optical photometry from 2.4-m and 0.5-m telescopes at the Thai National Observatory, and the 0.6-m PROMPT-8 telescope in Chile. Our TTV analysis allows us to place an upper mass limit for a second planet in the system. The presence of a hot Jupiter with a period of less than 10 days or a planet with an orbital period between 2.5 and 4.0 days are excluded. Combined optical and near-infrared transmission spectroscopy favour an H/He dominated haze (mean molecular weight 1.08$\pm$0.20) with high particle abundance at high altitude. We also argue that previous near-infrared data favour the presence of methane in the atmosphere of GJ3470b.

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S. Awiphan, E. Kerins, S. Pichadee, S. Komonjinda, V. S. Dhillon, W. Rujopakarn, S. Poshyachinda, T. R. Marsh, D. E. Reichart, K. M. Ivarsen, J. B. Haislip. 2016-09-20. Transit timing variation and transmission spectroscopy analyses of the hot Neptune GJ3470b. https://doi.org/10.1093/mnras%2Fstw2148

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