Physics – High Energy Physics – High Energy Physics - Phenomenology
Scientific paper
2008-04-02
Eur.Phys.J.A37:15-32,2008
Physics
High Energy Physics
High Energy Physics - Phenomenology
31 pages, 9 figures
Scientific paper
10.1140/epja/i2008-10600-0
We perform a theoretical study based on dispersion relations of the reaction \gamma\gamma\to \pi^0\pi^0 emphasizing the low energy region. We discuss how the f_0(980) signal emerges in \gamma\gamma\to \pi\pi within the dispersive approach and how this fixes to a large extent the phase of the isoscalar S-wave \gamma\gamma\to \pi\pi amplitude above the K\bar{K} threshold. This allows us to make sharper predictions for the cross section at lower energies and our results could then be used to distinguish between different \pi\pi isoscalar S-wave parameterizations with the advent of new precise data on \gamma\gamma\to\pi^0\pi^0. We compare our dispersive approach with an updated calculation employing Unitary Chiral Perturbation Theory (U\chiPT). We also pay special attention to the role played by the \sigma resonance in \gamma\gamma\to\pi\pi and calculate its coupling and width to gamma\gamma, for which we obtain \Gamma(\sigma\to\gamma\gamma)=(1.68\pm 0.15) KeV.
Oller Jose Antonio
Roca Luis
No associations
LandOfFree
Two photons into π^0π^0 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 Two photons into π^0π^0, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two photons into π^0π^0 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-389641