Ks-band light curve of CoRoT-1b

The eclipse shows a depth of 0.336+/-0.042% and is centered at phase 0.5022^+0.0023^_-0.0027_, consistent with a zero eccentricity orbit (e*cos{omega}=0.0035^+0.0036^_-0.0042_). We perform the first optical to near-infrared multi-band photometric analysis of an exoplanet's atmosphere and constrain the reflected and thermal emissions by combining our result with the recent 0.6, 0.71, and 2.09um secondary eclipse detections by Snellen et al. (2009Natur.459..543S), Gillon et al. (2009, J/A+A/506/359), and Alonso et al. (2009A&A...501L..23A).

Comparing the multi-wavelength detections to state-of-the-art radiative-convective chemical-equilibrium atmosphere models, we find the near-infrared fluxes difficult to reproduce. The closest blackbody-based and physical models provide the following atmosphere parameters: a temperature T=2460^+80^_-160_K; a very low Bond albedo A_B_=0.000^+0.081^_-0.000_; and an energy redistribution parameter P_n_=0.1, indicating a small but nonzero amount of heat transfer from the day to nightside.