Description
We report on new transit photometry for the super-Earth 55 Cnc e obtained with Warm Spitzer/IRAC at 4.5um. An individual analysis of these new data leads to a planet radius of 2.21^+0.15^_-0.16_R_{earth}_, in good agreement with the values previously derived from the MOST and Spitzer transit discovery data. A global analysis of both Spitzer transit time-series improves the precision on the radius of the planet at 4.5um to 2.20+/-0.12R_{earth}_. We also performed an independent analysis of the MOST data, paying particular attention to the influence of the systematic effects of instrumental origin on the derived parameters and errors by including them in a global model instead of performing a preliminary detrending-filtering processing. We deduce from this reanalysis of MOST data an optical planet radius of 2.04+/-0.15R_{earth}_ that is consistent with our Spitzer infrared radius
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