Accession Number : AD0290624

Title :   PION-PION INTERACTIONS IN THE STATES T EQUALS O AND T EQUALS 1

Corporate Author : UNIVERSITY COLL LONDON (ENGLAND)

Personal Author(s) : SPEARMAN,T.D.

Report Date : 29 AUG 1962

Pagination or Media Count : 1

Abstract : New dispersion relations are derived for the s-wave pion-nucleon scattering amplitudes. These relations are specifically chosen to facilitate the task of separating the two-pion exchange term from the other effects contributing to low energy pion-nucleon scattering. In these equations the contribution from the unknown short range terms is markedly suppressed, a greater emphasis is placed on the experimentally better established very low energy pion-nucleon data, (in particular, on the scattering lengths), and in the contribution of the twopion exchange term, the lower energies are more heavily stressed. The terms due to the two-pion exchange, which we isolate, are very clearly recognized by their characteristic energy dependences. The two-pion exchange terms are analyzed in terms of the interaction between the two pions. The values obtained for these terms are made to yield information about the phaseshifts for pion-pion scattering in the T=1 and T=0 states. In the T=1 state the data are well fitted with a narrow resonance in the pion-pion system at 750 Mev. Taking the results of electron-nucleon scattering experiments in conjunction with the present data, the half-width of this resonance is found to lie between 40 and 60 Mev, in agreement with the experimental data for the observed P-meson. (Author)

Descriptors :   *NUCLEAR FLUORESCENT SCATTERING, *PIONS, ENERGY, MESONS, PHASE SHIFT CIRCUITS, RESONANCE, SCATTERING

Distribution Statement : APPROVED FOR PUBLIC RELEASE