论文信息 - Positron and positronium studies of silica aerogel

Positron and positronium studies of silica aerogel

Variable-energy positron annihilation spectroscopy (VEPAS) has been used to probe the structure of gold nanoparticles suspended in a silica aerogel matrix by measuring the annihilation parameters S and W, and the ortho-positronium (o-Ps) fraction parameter F, as a function of incident positron energy. Correction methods have been developed to improve the sensitivity of F by removing background contributions to the number of recorded o-Ps annihilation events. Charging effects have also been observed and investigated.

T. Birks | P. G. Coleman | M. Grogan | C. Edwardson

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