Material testing with electron beams for neutrino factory targets

Solid targets for a 4 MW neutrino factory are required to withstand the pulsed power deposition of up to 1 MW (time averaged), at repetition rates of 10 to 100 Hz. Instantaneous energy depositions of over 100 J per gram are possible and the consequent temperature jump experienced by the target induces high levels of stress. Somewhat limited experience is available for the behaviour of materials under these extreme conditions, and clearly the lifetime of target material in constant shock is an important issue. To address this, tests of target materials are planned which reproduce the order of the peak energy density and most significantly, will provide information on cycle lifetime. By using high power, swept beams of electrons from a CW welding machine the power densities and repetition rates expected in a neutrino factory can be reproduced at modest cost