A planetary eclipse map of CoRoT-2a. Comprehensive lightcurve modeling combining rotational-modulation and transits

Abstract

We analyze the surface structure of the planet host star CoRoT-2a using a consistent model for both the `global' (i.e., rotationally modulated) lightcurve and the transit lightcurves, using data provided by the CoRoT mission. Selecting a time interval covering two stellar rotations and six transits of the planetary companion CoRoT-2b, we adopt a `strip' model of the surface to reproduce the photometric modulation inside and outside the transits simultaneously. Our reconstructions show that it is possible to achieve appropriate fits for the entire sub-interval using a low-resolution surface model with 36 strips. The surface reconstructions indicate that the brightness on the eclipsed section of the stellar surface is (6 +/- 1) % lower than the average brightness of the remaining surface. This result suggests a concentration of stellar activity in a band around the stellar equator similar to the behavior observed on the Sun.

accepted by A&A on 12/09/2009

References in corpus (4)

• The secondary eclipse of the transiting exoplanet CoRoT-2b
• Transit mapping of a starspot on CoRoT-2 - Probing a stellar surface by planetary transits
• Hubble Space Telescope Observations of SV Cam: I. The Importance of Unresolved Starspot Distributions in Lightcurve Fitting
• Magnetic activity in the photosphere of CoRoT-Exo-2a. Active longitudes and short-term spot cycle in a young Sun-like star

Cited by in corpus (11)

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• The corona and companion of CoRoT-2A. Insights from X-rays and optical spectroscopy
• How do starspots influence the transit timing variations of exoplanets? Simulations of individual and consecutive transits
• Observing dynamos in cool stars
• Signatures of Obliquity in Thermal Phase Curves of Hot Jupiters
• Glimpses of stellar surfaces. I. Spot evolution and differential rotation of the planet host star Kepler-210
• Glimpses of stellar surfaces. II. Origins of the photometric modulations and timing variations of KOI-1452
• Localizing flares to understand stellar magnetic fields and space weather in exo-systems