Temperature Dependence of Positron Mean Lives in Metals

The dependence of positron lifetimes on sample temperature has been studied in several metals over a range from room temperature to the melting point or to 400^∘{}C. Marked effects, amounting to as much as a 30% increase in lifetime, are noted in most of the low-melting-point metals. Lattice vacancies are considered to be the likely cause of these effects.