ISSN:
1432-0630
Keywords:
61.70
;
68.55
;
78.70
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Abstract The transmission through Al foils of isotropically implanted positrons from a22Naβ + source has been measured. It is shown that the transmission is reasonably well-described using an exponential profile once backscattering is accounted for, except for thicknesses below approximately 7 mg/cm2. Below this thickness, the measured transmission is slightly less than that predicted by the exponential profile. Such a deviation has previously been observed for collimated positrons, suggesting that the implantation profile has no significant dependence on the spatial distribution of the incident positrons. This deviation is critical for the proper interpretation of positron lifetime experiments on thin films using a conventional positron lifetime spectrometer.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01567885
