The secondary eclipse of CoRoT-1b

TL;DR

This paper reports the detection of the secondary eclipse of CoRoT-1b in optical wavelengths, providing insights into its temperature, orbit, and heat redistribution, using data from the CoRoT space telescope.

Contribution

First detection of CoRoT-1b's secondary eclipse in optical wavelengths, with analysis of its thermal emission and orbital parameters.

Findings

Eclipse depth of 0.016+/-0.006% detected

Eccentricity constrained to ecosomega<0.014

Estimated planetary temperature around 2330 K

Abstract

The transiting planet CoRoT-1b is thought to belong to the pM-class of planets, in which the thermal emission dominates in the optical wavelengths. We present a detection of its secondary eclipse in the CoRoT white channel data, whose response function goes from ~400 to ~1000 nm. We used two different filtering approaches, and several methods to evaluate the significance of a detection of the secondary eclipse. We detect a secondary eclipse centered within 20 min at the expected times for a circular orbit, with a depth of 0.016+/-0.006%. The center of the eclipse is translated in a 1-sigma upper limit to the planet's eccentricity of ecosomega<0.014. Under the assumption of a zero Bond Albedo and blackbody emission from the planet, it corresponds to a T_{CoRoT}=2330 +120-140 K. We provide the equilibrium temperatures of the planet as a function of the amount of reflected light. If the planet is in thermal equilibrium with the incident flux from the star, our results imply an inefficient transport mechanism of the flux from the day to the night sides.