Three - Quantum Annihilation in Porous Vycor Glass
نویسندگان
چکیده
f = τoPs/τoPs(vac), (1) where τoPs and τoPs(vac) are o-Ps lifetime in the sample and in vacuum, respectively. Three-quantum annihilation studies become competitive to the traditional positron annihilation lifetime spectrometry (PALS), in particular in the relation to porous media and positron beam technique [1]. Below we compare the results of estimation of 3γ intensity obtained by several classical methods. The measurements were performed with a set of porous Vycor glass samples in vacuum chamber (to eliminate ortho−para conversion in oxygen). Two samples of porous ordered silica (MCM-41) were also investigated. As a reference the nonporous Vycor glass was used.
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