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VLT transit and occultation photometry for the bloated planet CoRoT-1b

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 نشر من قبل Michael Gillon
 تاريخ النشر 2009
  مجال البحث فيزياء
والبحث باللغة English
 تأليف M. Gillon




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We present VLT eclipse photometry for the giant planet CoRoT-1b. We observed a transit in the R-band filter and an occultation in a narrow filter centered on 2.09 microns. Our analysis of this new photometry and published radial velocities, in combination with stellar-evolutionary modeling, leads to a planetary mass and radius of 1.07 (+0.13,-0.18) M_Jup and 1.45 (+0.07,-0.13) R_Jup, confirming the very low density previously deduced from CoRoT photometry. The large occultation depth that we measure at 2.09 microns (0.278 (+0.043,-0.066) %) is consistent with thermal emission and is better reproduced by an atmospheric model with no redistribution of the absorbed stellar flux to the night side of the planet.



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