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Dispersion relations along interior hyperbolas and a. set of hyperbolas passing through the Cheng-Dashen point are used to calculate the pion-nucleon sigma term. The t-channel input is updated using the recent GWU partial wave solution and n phase shifts from calculations based on Roy equations. Obtained values for the sigma term are still within the error bars of the previous Karlsruhe result. [ABSTRACT FROM AUTHOR]

In Hadžimehmedović et al. [Phys. Rev. C 84, 035204 (2011 )] we have used the Zagreb realization of Carnegie-Melon-Berkeley coupled-channel, unitary model as a tool for extracting pole positions from the world collection of partial-wave data, with the aim of eliminating model dependence in pole-search procedures, In order that the method is sensible, we in this paper discuss the stability of the method with respect to the strong variation of different model ingredients. We show that the Zagreb CMB procedure is very stable with strong variation of the model assumptions and that it can reliably predict the pole positions of the fitted partial-wave amplitudes. [ABSTRACT FROM AUTHOR]