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Study of $γπ\to ππ$ below 1 GeV using Integral Equation Approach

Tran N. Truong
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Abstract

The scattering of $γπ\to ππ$ is studied using the axial anomaly, elastic unitarity, analyticity and crossing symmetry. Using the technique to derive the Roy's equation, an integral equation for the P-wave amplitude is obtained in terms of the strong P-wave pion pion phase shifts. Its solution is obtained numerically by an iteration procedure using the starting point as the solution of the integral equation of the Muskelshsvilli-Omnes type. It is, however, ambiguous and depends sensitively on the second derivative of the P-wave amplitude at $s=m_π^2$ which cannot directly be measured.

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Tran N. Truong. 2001-10-03. Study of $γπ\to ππ$ below 1 GeV using Integral Equation Approach. https://doi.org/10.1103/physrevd.65.056004

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