2 research outputs found
Final-sate radiation in electron-positron annihilation into a pion pair
The process of annihilation into a pair with radiation
of a photon is considered. The amplitude of the reaction
consists of the model independent initial-state
radiation (ISR) and model-dependent final-state radiation (FSR). The general
structure of the FSR tensor is constructed from Lorentz covariance, gauge
invariance and discrete symmetries in terms of the three invariant functions.
To calculate these functions we apply Chiral Perturbation Theory (ChPT) with
vector and axial-vector mesons. The contribution of
process to the muon anomalous magnetic moment is evaluated, and results are
compared with the dominant contribution in the framework of a hybrid model,
consisting of VMD and point-like scalar eletrodynamics. The developed approach
allows us also to calculate the charge asymmetry.Comment: 21 pages, 8 figure