Evaluation of beta-decay. Pt. 5. The Z-independent outer radiative corrections for allowed decay

Before interpreting nuclear beta-decay in terms of nucleonic wave functions and weak coupling constants allowance must be made for the influence of virtual photon exchange and real photon emission together with Z-boson exchange - the radiative corrections. This paper discusses in detail the lowest order 'outer' radiative correction of Sirlin, energy-dependent but weak-interaction-mechanism-independent, and presents graphical and other material to enable its accurate evaluation for allowed decay for all beta-decay transition energies up to 20 MeV and for 0≤vertical stroke Zvertical stroke ≤100. The need to use electron spectra due to a nuclear charge distribution of finite spatial extension with appropriate convolution of the leptonic and nucleonic wave functions throughout the nuclear volume is emphasized; the variation of these effects between the neutron and proton drip lines is explored. Exponentiation and higher-order Z-independent effects are also considered. (orig.)