Abstract:
The contribution to the hyperfine shift of the positronium ground level is calculated to order
α6 on the basis of an expression for the polarization operator deduced from a quasipotential
equation.
Citation:
N. E. Nyun'ko, Yu. N. Tyukhtyaev, “Calculation of single-photon exchange diagrams in the quasipotential approach by means of the polarization operator”, TMF, 12:1 (1972), 56–63; Theoret. and Math. Phys., 12:1 (1972), 657–661