The ExoTETHyS package: Tools for Exoplanetary Transits around Host Stars

TL;DR

The ExoTETHyS package is an open-source Python toolkit that enhances modeling of exoplanet transits, offering high-precision tools for spectro-photometric observations crucial for upcoming space missions like JWST and ARIEL.

Contribution

It introduces a new stellar limb-darkening calculator with superior accuracy and an exact transit light-curve generator based on the stellar intensity profile.

Findings

Limb-darkening calculator outperforms existing software by tenfold in accuracy.

Provides an exact transit light-curve generator based on stellar intensity.

Essential tool for high-precision exoplanet atmospheric spectroscopy.

Abstract

We present here the first release of the open-source python package ExoTETHyS, which aims to provide a stand-alone set of tools for modeling spectro-photometric observations of the transiting exoplanets. In particular, we describe: (1) a new calculator of stellar limb-darkening coefficients that outperforms the existing software by one order of magnitude in terms of light-curve model accuracy, i.e., down to <10 parts per million (ppm); (2) an exact transit light-curve generator based on the entire stellar intensity profile rather than limb-darkening coefficients. New tools will be added in later releases to model various effects in exoplanetary transits and eclipsing binaries. ExoTETHyS is a reference package for high-precision exoplanet atmospheric spectroscopy with the upcoming JWST and ARIEL missions.