Non-thermal hard X-ray emission from stellar coronae

Non-thermal hard X-ray emission is a well known product of the most powerful flaring events observed in the solar corona. This emission is commonly explained with a ”non-thermal thick-target model”, where an electron beam generated after a magnetic reconnection event eventually hits the dense and warm plasma in the solar chromosphere. The quiescent X-ray emission level from young stellar objects or evolved active binaries can be higher than any solar flare, and these objects are also characterized by a more enhanced flaring activity. Yet, the detection of a non-thermal X-ray emission component in the stellar case remains elusive. I will show how the Simbol-X intrumentation will help us to investigate this issue, and hence to bring us unique information on the processes of energy release