1 Radiative decays

We consider the decay

where l stands for e or , and is a real photon with . Processes where the (virtual) photon converts into a or pair are considered in the next subsection. The mode is obtained from (1.1) by charge conjugation.

• 1.1 Matrix elements and kinematics
• 1.2 Decay rates
• 1.3 Determination of and
• 1.4 Previous experiments
• 1.5 Theory
• 1.6 Comment on tensor couplings
• 1.7 Improvements at DANE