论文信息 - Energy dependence of excited positronium formation at a molybdenum surface

Energy dependence of excited positronium formation at a molybdenum surface

The slow positron beam facility TEPOS at the 65 MeV electron linear accelerator in Giessen has been used to produce an intense beam of monoenergetic positrons. The impact energy of the positrons hitting the surface of a polycrystalline molybdenum foil has been varied between 0 and 470 eV. The authors observed the formation of n=2 positronium by the emitted Lyman- alpha radiation and its change as a function of the positron energy. They found a maximum yield of excited positronium at an implantation energy of (60+or-20) eV. The yield decreased to 50% of the maximum value at about 200 eV.

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