Analysis of the heat load of thin metal foil during electron beam scanning.

Abstract. The thermal loading of thin metal foils used as extraction windows in high current electron accelerators is one of the most important processes which should be analysed during the design of such devices. Heat loads at metal surface are also of special interest in many other plasma applications. The distribution of heat loads at the surface of thin metal foil is evaluated from the energy absorption in the foil and forced cooling with air flow. Time dependence of temperature distribution at the foil surface is calculated from the two-dimensional heat conduction equation. The simplified heat transient analysis is also given to determine the influence of scanning frequencies, electron beam size and shape ,shape of current impulses in scanning coils, energy loss in foil, the beam current and air cooling coefficient on time evolution of temperature for an arbitrary fixed point at the foil in first period of electron beam scanning. [ABSTRACT FROM AUTHOR]