Low-Energy D-Wave Effects in Neutral Pion Photoproduction

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 $\mathcal{O}(q^4)$, 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.

10 pages, 5 figures

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Cited by in corpus (9)

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• Model Selection for Pion Photoproduction
• Threshold ${\pi }^0$ photoproduction in relativistic chiral perturbation theory
• Upper Energy Limit of Heavy Baryon Chiral Perturbation Theory in Neutral Pion Photoproduction
• Unexpected impact of D waves in low-energy neutral pion photoproduction from the proton and the extraction of multipoles
• $\Delta (1232)$ resonance in the $\vec{\gamma }p\to p{\pi }^0$ reaction at threshold
• Neutral Pion Production in the Threshold Region
• New Analysis of Threshold Photoproduction Data from MAMI