Three-photon annihilation of the electron–positron pairs

Three-photon annihilation of the electron–positron pairs (=(e−,e+)=(e−,e+)-pairs) is considered in the electron rest frame. The energy of the incident positron can be arbitrary. The analytical expression for the cross-section of three-photon annihilation of the (e−,e+)(e−,e+)-pair has been derived and investigated.