A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2018; you can also visit the original URL.
The file type is application/pdf.
Low-energy photon–photon collisions to two loops revisited
2005
Nuclear Physics B
Preserved Fulltext
Other Versions
In view of ongoing experimental activities to determine the pion polarizabilities, we have started to recalculate the available two-loop expressions in the framework of chiral perturbation theory, because they have never been checked before. We make use of the chiral Lagrangian at order p^6 now available, and of improved techniques to evaluate the two-loop diagrams. Here, we present the result for the neutral pions. The cross section for the reaction gamma+gamma->pi0+pi0 agrees with the earlier
doi:10.1016/j.nuclphysb.2005.09.010
fatcat:mfbkti4qmzdhvmivvhaujngekq