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arXiv · 2210.09423

Towards the finite-volume spectrum of the Roper resonance

Daniel Severt
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Abstract

The finite-volume energy levels corresponding to the Roper resonance based on a two-flavor chiral effective Lagrangian at leading one-loop order are investigated. It is shown that the Roper mass can be extracted from these levels for not too large lattice volumes. Further, to include three-body $N \pi \pi$ dynamics, a non-relativistic effective field theory for the Roper resonance within a covariant particle-dimer picture is introduced. This particle-dimer approach is a suitable framework to investigate three-particle scattering relevant for the Roper channel. The appearing dimer fields are analyzed, the energy levels of the Roper resonance in a finite volume are calculated and compared to the results from the chiral effective Lagrangian.

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Daniel Severt. 2022-10-17. Towards the finite-volume spectrum of the Roper resonance. https://arxiv.org/abs/2210.09423

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