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arXiv · 0902.3412

Low-Energy D-Wave Effects in Neutral Pion Photoproduction

C. Fernandez-Ramirez·A. M. Bernstein·T. W. Donnelly
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Abstract

The contribution of D waves to physical observables for neutral pion photoproduction in the near threshold region is studied. Heavy Baryon Chiral Perturbation Theory to one loop, and up to ${\cal O}(q^4)$, is used to account for the S and P waves, while D waves are added in an almost model-independent way using standard Born terms and vector mesons. It is found that the inclusion of D waves is necessary to extract the $E_{0+}$ multipole reliably from present and forthcoming data and to assess the low-energy constants of Chiral Perturbation Theory. Arguments are presented demonstrating that F-wave contributions are negligible in the near-threshold region.

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C. Fernandez-Ramirez, A. M. Bernstein, T. W. Donnelly. 2009-07-16. Low-Energy D-Wave Effects in Neutral Pion Photoproduction. https://doi.org/10.1016/j.physletb.2009.07.011

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