Moment–operator expansion for the two-meson, two-photon and fermion-antifermion states
نویسنده
چکیده
A complete set of formulae in terms of the moment–operator expansion is presented for the two-meson, two-photon and fermion-antifermion states that can be used in the analysis of scalar (S) and pseudoscalar (P ) meson production in pp̄ and γγ collisions: pp̄ → SS,PP, SP and γγ → SS,PP, SP . Method of a generalization of the formulae for amplitudes of multi-meson production in the two-stage processes of the type (spin-j) resonance + meson → three mesons is also discussed.
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