Dynamics of Internally Converted ElectronPositron Pairs
Abstract
The reactions studied were π^{}+p>n+π^{0} (π^{0}>γ+e^{+}+e^{}) and π^{}+p>n+e^{+}+e^{}. From a sample of ~15 000 internally converted electronpositron pairs, 7000 were measured, of which 4200 were used in the detailed analysis. The differential distributions in y (the energy partition) and x^{2} (the virtual mass of the photon) agree with the theoretical quantum electrodynamic calculations. A measure of the form factor for the π^{0}>2γ reaction gave a value Γ(xμ)=1(0.24+/0.16)x^{2}μ^{2}, where μ is the mass of the pion. It was further demonstrated that the number of events necessary to determine the contribution of the longitudinally polarized virtual γ rays in the second reaction is of the order of 50 times that in the present experiment.
 Publication:

Physical Review
 Pub Date:
 January 1961
 DOI:
 10.1103/PhysRev.121.275
 Bibcode:
 1961PhRv..121..275S