Atmospheric retrievals with petitRADTRANS

TL;DR

petitRADTRANS is a fast radiative transfer tool that now includes a retrieval module, enabling efficient atmospheric characterization of exoplanets through spectral fitting using nested sampling.

Contribution

The paper introduces a new retrieval module for petitRADTRANS that integrates fast forward modeling with nested sampling for exoplanet atmospheric analysis.

Findings

Enables quick and accurate atmospheric retrievals for various exoplanet types.

Widely adopted in the exoplanet community with extensive benchmarking.

Facilitates analysis of both transmission and emission spectra.

Abstract

petitRADTRANS (pRT) is a fast radiative transfer code used for computing emission and transmission spectra of exoplanet atmospheres, combining a FORTRAN back end with a Python based user interface. It is widely used in the exoplanet community with 222 references in the literature to date, and has been benchmarked against numerous similar tools. The spectra calculated with pRT can be used as a forward model for fitting spectroscopic data using Monte Carlo techniques, commonly referred to as an atmospheric retrieval. The new retrieval module combines fast forward modelling with nested sampling codes, allowing for atmospheric retrievals on a large range of different types of exoplanet data. Thus it is now possible to use pRT to easily and quickly infer the atmospheric properties of exoplanets in both transmission and thermal emission.