High-energy irradiation of exoplanets has been identified to be a key influence on the stability of these planets ’ atmospheres .
So far , irradiation-driven mass-loss has been observed only in two Hot Jupiters , and the observational data remain even more sparse in the super-earth regime .
We present an investigation of the high-energy emission in the CoRoT-7 system , which hosts the first known transiting super-earth .
To characterize the high-energy XUV radiation field into which the rocky planets CoRoT-7b and CoRoT-7c are immersed , we analyzed a 25 ks XMM- Newton observation of the host star .
Our analysis yields the first clear ( 3.5 \sigma ) X-ray detection of CoRoT-7 .
We determine a coronal temperature of \approx 3 MK and an X-ray luminosity of 3 \times 10 ^ { 28 } erg s ^ { -1 } .
The level of XUV irradiation on CoRoT-7b amounts to \approx 37 000 erg cm ^ { -2 } s ^ { -1 } .
Current theories for planetary evaporation can only provide an order-of-magnitude estimate for the planetary mass loss ; assuming that CoRoT-7b has formed as a rocky planet , we estimate that CoRoT-7b evaporates at a rate of about 1.3 \times 10 ^ { 11 } g s ^ { -1 } and has lost \approx 4 - 10 earth masses in total .