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The N*(1520) ---> Delta pi Amplitudes Extracted from the gamma p ---> pi+ pi- p Reaction and Comparison to Quark Models

J. A. Gomez Tejedor·F. Cano·E. Oset
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Abstract

The gamma p ---> pi+ pi- p reaction, in combination with data from the pi N ---> pi pi N reaction, allows one to obtain the s- and d-wave amplitudes for the N*(1520) decay into Delta pi with absolute sign with respect to the N*(1520) ---> N gamma helicity amplitudes. In addition one obtains the novel information on the q dependence of the amplitudes. This dependence fits exactly with the predictions of the non-relativistic constituent quark models. The absolute values provided by these models agree only qualitatively, and a discussion is done on the reasons for it and possible ways to improve.

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J. A. Gomez Tejedor, F. Cano, E. Oset. 1996-03-20. The N*(1520) ---> Delta pi Amplitudes Extracted from the gamma p ---> pi+ pi- p Reaction and Comparison to Quark Models. https://doi.org/10.1016/0370-2693(96)00404-2

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