P -wave excited baryons from pion- and photo-induced hyperon production
Helmholtz-Institut für Strahlen- und Kernphysik, Universität Bonn, Bonn, Germany
2 Petersburg Nuclear Physics Institute, Gatchina, Russia
Accepted: 26 January 2011
Published online: 24 February 2011
We report evidence for N(1710)P 11 , N(1875)P 11 , N(1900)P 13 , (1600)P 33 , (1910)P 31 , and (1920)P 33 , and find indications that N(1900)P 13 might have a companion state at 1970MeV. The controversial (1750)P 31 is not seen. The evidence is derived from a study of data on pion- and photo-induced hyperon production, but other data are included as well. Most of the resonances reported here were found in the Karlsruhe-Helsinki (KH84) and the Carnegie-Mellon (CM) analyses but were challenged recently by the Data Analysis Center at GWU. Our analysis is constrained by the energy-independent N scattering amplitudes from either KH84 or GWU. The two N amplitudes from KH84 or GWU, respectively, lead to slightly different N branching ratios of contributing resonances but the debated resonances are required in both series of fits.
© SIF, Springer-Verlag Berlin Heidelberg, 2011