Processes Involving Pair Production
The process of electron positron pair production has been investigated for many years with the earliest studies considering the creation of a free pair by highly energetic X-rays and the closely related Bremsstrahlung. We shall see later how these two processes are connected by crossing symmetries. The non-relativistic Bremsstrahlung problem was solved exactly by Sommerfeld (1931) and at relativistic energies, cross sections were originally obtained by Bethe and Heitler (1934) using the Born approximation. A detailed investigation of both processes was carried out by Bethe and Maximon (1954) where the free leptons were described by Furry wavefunctions. Attempts to describe, theoretically, the production of an e –/e + pair during the collision of two heavy particles began in the 1930s and have often used the virtual photon method of Weizsäcker (1934) and Williams (1934). Early references can be found in Heitler (1954), while more recent papers on this method are Soff (1980), and Nikishov and Pichkurov (1982). Anholt et al (1983) calculated cross sections for the direct pair production process at non-relativistic energies and this was extended into the relativistic region by Becker et al (1986) using Dirac wavefunctions.
KeywordsTotal Cross Section Electron Capture Differential Cross Section Lepton Pair Antihydrogen Atom
Unable to display preview. Download preview PDF.