On the Inclination Dependence of Exoplanet Phase Signatures

TL;DR

This paper explores how orbital inclination affects the phase signatures of eccentric exoplanets, aiding in the selection of optimal observation angles for future space-based coronagraphic studies.

Contribution

It extends previous phase function studies by analyzing inclination effects on flux ratios and projected separations for eccentric exoplanets.

Findings

Optimal inclinations for maximum flux ratios identified.

Calculations applicable to current and future coronagraph observations.

Potential target exoplanets for phase signature studies highlighted.

Abstract

Improved photometric sensitivity from space-based telescopes have enabled the detection of phase variations for a small sample of hot Jupiters. However, exoplanets in highly eccentric orbits present unique opportunities to study the effects of drastically changing incident flux on the upper atmospheres of giant planets. Here we expand upon previous studies of phase functions for these planets at optical wavelengths by investigating the effects of orbital inclination on the flux ratio as it interacts with the other effects induced by orbital eccentricity. We determine optimal orbital inclinations for maximum flux ratios and combine these calculations with those of projected separation for application to coronagraphic observations. These are applied to several of the known exoplanets which may serve as potential targets in current and future coronagraph experiments.