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Search for rings and satellites around the exoplanet CoRoT-9b using Spitzer photometry

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 نشر من قبل Alain Lecavelier des Etangs
 تاريخ النشر 2017
  مجال البحث فيزياء
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Using Spitzer photometry at 4.5 microns, we search for rings and satellites around the long period transiting planet CoRoT-9b. We observed two transits in 2010 and 2011. From their non-detection, we derive upper limits on the plausible physical characteristics of these objects in the planet environment. We show that a satellite larger than about 2.5 Earth radii is excluded at 3-$sigma$ for a wide range of elongations at the two epochs of observations. Combining the two observations, we conclude that rings are excluded for a wide variety of sizes and inclination. We find that for a ring extending up to the Roche limit, its inclination angle from the edge-on configuration as seen from the Earth must be lower than 13{deg} in the case of silicate composition and lower than 3{deg} in the case of material with water ice density.



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