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arXiv · hep-ph/0006016

Parapositronium Decay and Dispersion Relations

G. Lopez Castro·J. Pestieau·C. Smith·S. Trine
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Abstract

Positronium decay rates are computed at the one-loop level, using convolution-type factorized amplitudes. The dynamics of this factorization is probed with dispersion relations, showing that unallowed approximations are usually made, and some ordre alpha^2 corrections missed. Further, we discuss the relevance of the Schrodinger wavefunction as the basis for perturbative calculations. Finally, we apply our formalism to the parapositronium two-photon decay.

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G. Lopez Castro, J. Pestieau, C. Smith, S. Trine. 2000-06-01. Parapositronium Decay and Dispersion Relations. https://arxiv.org/abs/hep-ph/0006016

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