Transiting exoplanets from the CoRoT space mission. VII. The “hot-Jupiter”-type planet CoRoT-5b

Abstract

Aims. The CoRoT space mission continues to photometrically monitor about 12,000 stars in its field-of-view for a series of target fields to search for transiting extrasolar planets ever since 2007. Deep transit signals can be detected quickly in the “alarm-mode” in parallel to the ongoing target field monitoring. CoRoT’s first planets have been detected in this mode. Methods. The CoRoT raw lightcurves are filtered for orbital residuals, outliers, and low-frequency stellar signals. The phase folded lightcurve is used to fit the transit signal and derive the main planetary parameters. Radial velocity follow-up observations were initiated to secure the detection and to derive the planet mass. Results. We report the detection of CoRoT-5b, detected during observations of the LRa01 field, the first long-duration field in the galactic anticenter direction. CoRoT-5b is a “hot Jupiter-type” planet with a radius of 1.388+0.046−0.047 RJup, amass of 0.467+0.047−0.024 MJup, and therefore, a mean density of 0.217+0.031−0.025 g cm−3. The planet orbits an F9V star of 14.0 mag in 4.0378962 ± 0.0000019 days at an orbital distance of 0.04947+0.00026−0.00029 AU.