Analysis of the low-energy ${\pi }^{\pm }p$ differential cross sections of the CHAOS Collaboration

Abstract

This paper presents the results of an analysis of the low-energy ${\pi }^{\pm }p$ differential cross sections, acquired by the CHAOS Collaboration at TRIUMF \cite{chaos,denz}. We first analyse separately the ${\pi }^{+}p$ and the ${\pi }^{-}p$ elastic-scattering measurements on the basis of standard low-energy parameterisations of the $s$- and p-wave $K$-matrix elements. After the removal of the outliers, we subject the truncated ${\pi }^{\pm }p$ elastic-scattering databases into a common optimisation scheme using the ETH model \cite{glmbg}; the optimisation failed to produce reasonable values for the model parameters. We conclude that the problems we have encountered in the analysis of these data are due to the shape of the angular distributions of their ${\pi }^{+}p$ differential cross sections.

References in corpus (9)

• CODATA Recommended Values of the Fundamental Physical Constants: 2010
• Extended Partial-Wave Analysis of piN Scattering Data
• Global analysis of proton elastic form factor data with two-photon exchange corrections
• Improved description of the $\pi N$-scattering phenomenology in covariant baryon chiral perturbation theory
• Phase-shift analysis of low-energy ${\pi }^{\pm }p$ elastic-scattering data
• Evaluation of the Pion-Nucleon Sigma Term from CHAOS Data
• Determination of the s-wave pion-nucleon threshold scattering parameters from the results of experiments on pionic hydrogen
• Aspects of the ETH model of the pion-nucleon interaction
• Analysis of the low-energy ${\pi }^{\pm }p$ elastic-scattering data

Cited by in corpus (3)

• Aspects of the ETH model of the pion-nucleon interaction
• Analysis of the low-energy ${\pi }^{-}p$ charge-exchange data
• Systematic effects in the low-energy behavior of the current SAID solution for the pion-nucleon system