Positronium Decay : Gauge Invariance and Analyticity

Simple item page
dc.creatorPestieau, J.
dc.creatorSmith, C.
dc.creatorTrine, S.
dc.date2001-05-03
dc.date.accessioned2026-07-07T11:31:06Z
dc.date.available2026-07-07T11:31:06Z
dc.descriptionThe construction of positronium decay amplitudes is handled through the use of dispersion relations. In this way, emphasis is put on basic QED principles: gauge invariance and soft-photon limits (analyticity). A firm grounding is given to the factorization approaches, and some ambiguities in the spin and energy structures of the positronium wavefunction are removed. Non-factorizable amplitudes are naturally introduced. Their dynamics is described, especially regarding the enforcement of gauge invariance and analyticity through delicate interferences. The important question of the completeness of the present theoretical predictions for the decay rates is then addressed. Indeed, some of those non-factorizable contributions are unaccounted for by NRQED analyses. However, it is shown that such new contributions are highly suppressed, being of order alpha^3. Finally, a particular effective form factor formalism is constructed for parapositronium, allowing a thorough analysis of binding energy effects and analyticity implementation.
dc.description34 pages, 13 figures
dc.identifierhttps://arxiv.org/abs/hep-ph/0105034
dc.identifierhttp://arxiv.org/abs/hep-ph/0105034
dc.identifierInt.J.Mod.Phys.A17:1355-1398,2002
dc.identifierdoi:10.1142/S0217751X02009606
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/197161
dc.subjectHigh Energy Physics - Phenomenology
dc.titlePositronium Decay : Gauge Invariance and Analyticity
dc.typetext

Files

Collections

arXiv