Positron production using a 1.7 MV pelletron accelerator

We report the foremost phase of a fourth generation positron source, being constructed at the Federal University of Rio de Janeiro. Positron yields are reported by making use of the 19F(p,αe+e−)16O reaction, where the fluorine target is in the form of a CaF2 pellet. Positron production has been observed by detecting 511 keV annihilation gamma rays emerging from the irradiated CaF2 target.