The energies and residues of the nucleon resonances N(1535) and N(1650)

Arndt, R. A.; Green, A. M.; Workman, R. L.; Wycech, S.

The energies and residues of the nucleon resonances N(1535) and N(1650)

Authors

Description

We extract pole positions for the N(1535) and N(1650) resonances using two different models. The positions are determined from fits to different subsets of the existing $πN\toπN$, $πN\toηN$ and $γp\toηp$ data and found to be 1515(10)--i85(15)MeV and 1660(10)--i65(10)MeV, when the data is described in terms of two poles. Sensitivity to the choice of fitted data is explored. The corresponding $ππ$ and $ηη$ residues of these poles are also extracted.
9 pages