Ratio of the real and imaginary parts of the
scattering amplitude near the
threshold
Dal'karov O. D., Protasov K. V.
The appearance of a maximum in the observed momentum dependence of the ratio of the real and imaginary parts of the amplitude for forward pp scattering in the range 0-200 MeV/c of the momentum of the incident antiproton is explained. It results from the opening of the Tin channel and the rapid growth of, and the relatively large magnitude of, the P-wave component of low-energy AW scattering.