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arXiv · 1606.04873

The width of the Roper resonance in baryon chiral perturbation theory

Jambul Gegelia·Ulf-G. Meißner·De-Liang Yao
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Abstract

We calculate the width of the Roper resonance at next-to-leading order in a systematic expansion of baryon chiral perturbation theory with pions, nucleons, and the delta and Roper resonances as dynamical degrees of freedom. Three unknown low-energy constants contribute up to the given order. One of them can be fixed by reproducing the empirical value for the width of the Roper decay into a pion and a nucleon. Assuming that the remaining two couplings of the Roper interaction take values equal to those of the nucleon, the result for the width of the Roper decaying into a nucleon and two pions is consistent with the experimental value.

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Jambul Gegelia, Ulf-G. Meißner, De-Liang Yao. 2016-06-15. The width of the Roper resonance in baryon chiral perturbation theory. https://doi.org/10.1016/j.physletb.2016.07.068

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