Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2007-05-09
Nucl.Phys.B788:21-46,2008
Physics
High Energy Physics
High Energy Physics - Phenomenology
28 pages, 5 figures; typos corrected, one reference added, published version
Scientific paper
10.1016/j.nuclphysb.2007.07.013
The orthopositronium decay to three photons is studied in the phase-space region where one of the photons has an energy comparable to the relative three-momentum of the e+e- system (w ~ m alpha). The NRQED computation in this regime shows that the dominant contribution arises from distances ~ 1/(mw)^(1/2), which allows to treat the Coulomb interaction perturbatively. The small-photon energy expansion of the 1-loop decay spectrum from full QED yields the same result as the effective theory. By doing the threshold expansion of the 1-loop QED amplitude we confirm that the leading term arises from a loop-momentum region where q^0 ~ q^2/m ~ w. This corresponds to a new non-relativistic loop-momentum region, which has to be taken into account for the description of a non-relativistic particle-antiparticle system that decays through soft photon emission.
No associations
LandOfFree
The soft-energy region in the radiative decay of bound states does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The soft-energy region in the radiative decay of bound states, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The soft-energy region in the radiative decay of bound states will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-646243