Toward the Analysis of JWST Exoplanet Spectra: the effective temperature in the context of direct imaging

TL;DR

This paper investigates how JWST exoplanet spectra can be used to accurately determine effective temperatures, reducing uncertainties and improving atmospheric models through optimized wavelength coverage analysis.

Contribution

It introduces a method to infer effective temperature from JWST spectra, highlighting key wavelength ranges to minimize uncertainties and enhance atmospheric modeling accuracy.

Findings

Wavelength coverage is crucial for accurate temperature estimation.

JWST spectra can achieve uncertainties comparable to or better than current methods.

Optimized wavelength analysis improves exoplanet atmospheric modeling.

Abstract

The current sparse wavelength range coverage of exoplanet direct imaging observations, and the fact that models are defined using a finite wavelength range, lead both to uncertainties on effective temperature determination.We study these effects using black-bodies and atmospheric models and we detail how to infer this parameter. Through highlighting the key wavelength coverage that allows for a more accurate representation of the effective temperature, our analysis can be used to mitigate or manage extra uncertainties being added in the analysis from the models. We find that the wavelength range coverage will soon no longer be a problem. An effective temperature computed by integrating the spectroscopic observations of the James Webb Space Telescope (JWST) will give uncertainties similar to, or better than, the current state-of-the-art, which is to fit models to data. Accurately calculating the effective temperature will help to improve current modelling approaches. Obtaining an independent and precise estimation of this crucial parameter will help the benchmarking process to identify the best practice to model exoplanet atmospheres.