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arXiv · hep-ph/9606456

Systematic 1/M Expansion for Spin 3/2 Particles

Thomas R. Hemmert·Barry R. Holstein·Joachim Kambor
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Abstract

Starting from a relativistic formulation of the pion-nucleon-delta system, the most general structure of 1/M corrections for a heavy baryon chiral lagrangian including spin 3/2 resonances is given. The heavy components of relativistic nucleons and delta fields are integrated out and their contributions to the next-to-leaing order lagrangians are constructed explicitly. The effective theory obtained admits a systematic expansion in terms of soft momenta, the pion mass $m_π$ and the delta-nucleon mass difference $Δ$. As an application, we consider neutral pion photoproduction at threshold to third order in this small scale expansion.

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Thomas R. Hemmert, Barry R. Holstein, Joachim Kambor. 1996-12-11. Systematic 1/M Expansion for Spin 3/2 Particles. https://doi.org/10.1016/s0370-2693(97)00049-x

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