Prog. Theor. Phys. Vol. 46 No. 3 (1971) pp. 846-856
Spinor Ladder Models and the Asymptotic Behavior of Neutral Pion Photoproduction Amplitudes
Department of Physics, University of Tokyo, Tokyo
(Received May 11, 1971)
The asymptotic behaviors of nucleon-antinucleon scattering and π0-photoproduction off a proton are calculated in perturbative ladder models whose sides are both spinor lines. Spins of the particles are treated correctly. Non-integer fixed branch points of the square-root type in complex angular momentum plane are found to dominate the amplitudes when s goes to minus infinity with t fixed. This disproves the previous conjecture that the right signature fixed pole at J=0 may dominate the π0-photoproduction amplitude in the spinor ladder model, and seems to make the fixed pole unstatisfactory in explaning the experimental behavior s2dσ/dt=constant.
DOI : 10.1143/PTP.46.846
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Citing Article(s) :
Progress of Theoretical Physics Vol. 47 No. 6 (1972) pp. 1898-1909
Cut Contributions to the Neutral Pion Photoproduction in the Dual Cut Model
Tetsuro Kobayashi and Kenji Yamagishi