The Hubble PanCET program: Emission spectrum of hot Jupiter HAT-P-41b

TL;DR

This study provides a comprehensive emission spectrum of hot Jupiter HAT-P-41b, revealing a near blackbody emission profile consistent with an isothermal atmosphere and offering insights into its thermal structure and composition.

Contribution

It combines new HST and archival Spitzer data to produce the most complete emission spectrum of HAT-P-41b, advancing understanding of its atmospheric properties.

Findings

Near blackbody-like emission spectrum observed

Best fitted with an isothermal temperature-pressure profile

No significant H$^-$ opacity or metal-rich atmosphere detected

Abstract

We present the most complete emission spectrum for inflated hot Jupiter HAT-P-41b combining new HST WFC/G141 spectrum from the Hubble Panchromatic Comparative Exoplanet Treasury (PanCET) program with archival Spitzer eclipse observations. We found a near blackbody-like emission spectrum which is best fitted with an isothermal temperature-pressure (TP) profile that agrees well with the dayside heat redistribution scenario assuming zero Bond albedo. The non-inverted TP profile is consistent with the non-detection of NUV/optical absorbers in the transit spectra. We do not find any evidence for significant H$^-$ opacity nor a metal-rich atmosphere. HAT-P-41b is an ideal target that sits in the transitioning parameter space between hot and ultra-hot Jupiters, and future JWST observations will help us to better constrain the thermal structure and chemical composition.