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Status of Nucleon Resonances with Masses $M<M_N+M_π$

R. Beck·S. N. Cherepnya·L. V. Fil'kov·V. L. Kashevarov·M. Rost·Th. Walcher
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Abstract

We discuss different interpretations of peaks observed a few years ago by Tatischeff et al. in missing mass spectra of the reaction $pp->pi^+pX$, which were declared as new exited nucleon states with small masses. A study of the possible production of such states in the process $γp->pi^+N^*->pi^+ +γγn$ by analyzing the invariant mass spectrum of $γγn$ is proposed. It is shown that the data, obtained recently at MAMI-B, can allow to analyze this process and to get information about an existence of exited nucleon states with small masses.

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R. Beck, S. N. Cherepnya, L. V. Fil'kov, V. L. Kashevarov, M. Rost, Th. Walcher. 2001-04-24. Status of Nucleon Resonances with Masses $M<M_N+M_π$. https://doi.org/10.1142/9789812810878_0038

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