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Is The Heavy Fermion Formalism Applicable to Meson Production Process?

E. Gedalin·A. Moalem·L. Razdolskaya
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Abstract

We consider tree diagram contributions to neutral pion production in pp ->pp pi0 using chiral perturbation theory in the relativistic and extremely non-relativistic limits. In marked difference with the results from heavy fermion formalism, the impulse and s-wave rescattering terms in the relativistic limit have equal signs and therefore add constructively, giving rise to a substantial contribution to the cross section. We argue that the power series expansion of the nucleon propagator is on the border of its convergence circle. Consequently, a finite order heavy fermion formalism does not predict nucleon pole terms correctly and therefore can not be applied to meson production.

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E. Gedalin, A. Moalem, L. Razdolskaya. 1998-12-02. Is The Heavy Fermion Formalism Applicable to Meson Production Process?. https://arxiv.org/abs/nucl-th/9812009

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