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Comment on `Measurement of the $π^+ \vec p$ analyzing power at 68.3 MeV'

R. A. Arndt·I. I. Strakovsky·R. L. Workman
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Abstract

We comment on a recent paper by Weiser et al. [Phys. Rev. C {\bf 54}, 1930 (1996)]. The authors have performed a single-energy analysis of $π^+ p$ scattering data at 68.3 MeV, finding a value for the $S_{31}$ phase shift about 1^o smaller than found in the Karlsruhe-Helsinki (KH) partial-wave analysis. The authors use this result to argue for a dispersion relation analysis using recently measured data, so that their effect on the $πNN$ coupling constant (f^2) and $Σ$ amplitude can be determined. We note that these tasks were accomplished prior to the submission of the above paper. We clarify the effect of this new analyzing power data on f^2 and the $Σ$ amplitude.

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R. A. Arndt, I. I. Strakovsky, R. L. Workman. 1997-02-27. Comment on `Measurement of the $π^+ \vec p$ analyzing power at 68.3 MeV'. https://doi.org/10.1103/physrevc.56.579

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