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arXiv · hep-ex/0308031

Solution of Orthopositronium lifetime Puzzle

S. Asai·O. Jinnouchi·T. Kobayashi
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Abstract

The intrinsic decay rate of orthopositronium formed in ${\rm SiO_2}$ powder is measured using the direct $2γ$ correction method such that the time dependence of the pick-off annihilation rate is precisely determined. The decay rate of orthopositronium is found to be $7.0396\pm0.0012 (stat.)\pm0.0011 (sys.)μs^{-1}$, which is consistent with our previous measurements with about twice the accuracy. Results agree well with the $O(α^2)$ QED prediction, and also with a result reported very recently using nanoporous film.

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S. Asai, O. Jinnouchi, T. Kobayashi. 2003-08-11. Solution of Orthopositronium lifetime Puzzle. https://doi.org/10.1142/s0217751x0402018x

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