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arXiv · 0804.1531

Test of isospin symmetry via low energy $^1$H($π^-$,$π^o$)$n$ charge exchange

Y. Jia·T. P. Gorringe·M. D. Hasinoff·M. A. Kovash·M. Ojha·M. M. Pavan·S. Tripathi·P. A. Zolnierczuk
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Abstract

We report measurements of the $π^- p \to π^o n$ differential cross sections at six momenta (104-143 MeV/c) and four angles (0-40 deg) by detection of $γ$-ray pairs from $π^o \to γγ$ decays using the TRIUMF RMC spectrometer. This region exhibits a vanishing zero-degree cross section from destructive interference between s-- and p--waves, thus yielding special sensitivity to pion-nucleon dynamics and isospin symmetry breaking. Our data and previous data do not agree, with important implications for earlier claims of large isospin violating effects in low energy pion-nucleon interactions.

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Y. Jia, T. P. Gorringe, M. D. Hasinoff, M. A. Kovash, M. Ojha, M. M. Pavan, S. Tripathi, P. A. Zolnierczuk. 2008-04-09. Test of isospin symmetry via low energy $^1$H($π^-$,$π^o$)$n$ charge exchange. https://doi.org/10.1103/physrevlett.101.102301

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