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arXiv · 1509.04847

Above-Threshold Poles in Model-Independent Form Factor Parametrizations

Benjamin Grinstein·Richard F. Lebed
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Abstract

The model-independent parametrization for exclusive hadronic form factors commonly used for semileptonic decays is generalized to allow for the inclusion of above-threshold resonant poles of known mass and width. We discuss the interpretation of such poles, particularly with respect to the analytic structure of the relevant two-point Green's function in which they reside. Their presence has a remarkably small effect on the parametrization, as we show explicitly for the case of $D \to πe^+ ν_e$.

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Benjamin Grinstein, Richard F. Lebed. 2015-11-25. Above-Threshold Poles in Model-Independent Form Factor Parametrizations. https://doi.org/10.1103/physrevd.92.116001

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