Sb. Shrivastava et K. Agrawal, IMPLANTATION PROFILE AND POSITRONIUM FRACTION FOR LOW-ENERGY POSITRONS, Physica status solidi. b, Basic research, 182(2), 1994, pp. 347-355
The diffusion equation for positrons is solved subjected to two types
of implantation profiles, namely, exponential and derivative of Gaussi
an type. The positronium fraction obtained using the two profiles has
been compared with experimental results. It is found that in general,
the use of the derivative of the Gaussian-type profile gives better re
sults. The maximum yield of the positronium as a function of temperatu
re is predicted corresponding to the different orientations of the alu
minum surface.