G. Lopez Castro, J. Pestieau, C. Smith, S. Trine
Published 2000-06-01Version 1
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.
Comments: LaTeX, 13 pages, 1 eps figure
Unitarity, analiticity, dispersion relations and resonances in strongly interacting $W_L W_L$, $Z_L Z_L$ and $hh$ scattering
O(alpha^3 ln alpha) corrections to positronium decay rates
alpha^2 corrections to parapositronium decay: a detailed description
