A dynamic beam window for coupling accelerator and reactor core in an ADS

During the many fruitful discussions and presentations at this EUCARD2-workshop we all were once more reminded of the respective technical short comings of the two solutions bringing an intense proton-beam on a molten-lead spallation target housed inside a fuel-loaded reactor. These are namely the window-less target solution where the accelerator is completely unprotected from accidentally back-streaming target material or the window solution with it’s inherent danger of catastrophic failure. We incidentally note how elegant the ESS spallation target circumvents all problems as shown at this EUCARD2 workshop, however, for evident reasons of size and geometry, it is not possible to lodge such a target inside the core of a subcritical reactor.