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arXiv · 1603.07265

Correlations of $\boldsymbol{\pi N}$ Partial Waves for Multi-Reaction Analyses

M. Döring·J. Revier·D. Rönchen·R. Workman
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Abstract

In the search for missing baryonic resonances, many analyses include data from a variety of pion- and photon-induced reactions. For elastic $\pi N$ scattering, however, usually the partial waves of the SAID or other groups are fitted, instead of data. We provide the partial-wave covariance matrices needed to perform correlated $\chi^2$ fits, in which the obtained $\chi^2$ equals the actual $\chi^2$ up non-linear and normalization corrections. For any analysis relying on partial waves extracted from elastic pion scattering, this is a prerequisite to assess the significance of resonance signals and to assign any uncertainty on results. The influence of systematic errors is also considered.

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M. Döring, J. Revier, D. Rönchen, R. Workman. 2016-03-23. Correlations of $\boldsymbol{\pi N}$ Partial Waves for Multi-Reaction Analyses. https://doi.org/10.1103/physrevc.93.065205

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