The Munich Intense POsitron Source (MIPOS) facility for producing a high intense positron beam at the new Munich research reactor (Forschungs-Reaktor Muenchen II) FRM-II is presented. Positrons are generated by pair production of high energy prompt γ-rays from neutron capture in cadmium: 113Cd(n; γ)114Cd. A cadmium cap will be located inside a beamtube at an undisturbed thermal neutron flux of 2×1014 n cm-2 s-1. Model calculation showed that this would lead to a mean capture rate of 1.2×1013 n cm-2 s-1. Thermal load resulting from absorbed γ-rays is expected to be less than 4 W cm-2. Inside the cadmium cap a structure of platinum and a stack of tungsten foils is placed for converting the γ-rays into positron-electron pairs. Platinum is used as converting material, since the cross section for pair production is even higher (+11    «

The Munich Intense POsitron Source (MIPOS) facility for producing a high intense positron beam at the new Munich research reactor (Forschungs-Reaktor Muenchen II) FRM-II is presented. Positrons are generated by pair production of high energy prompt γ-rays from neutron capture in cadmium: 113Cd(n; γ)114Cd. A cadmium cap will be located inside a beamtube at an undisturbed thermal neutron flux of 2×1014 n cm-2 s-1. Model calculation showed that this would lead to a mean capture rate of 1.2×1013 n...    »