Fernández Ramírez, CésarBernstein, Aaron M.Donnelly, T. W.2024-12-092024-12-092009-08-10Fernández-Ramírez, Bernstein, & Donnelly. (2009). Low-energy D-wave effects in neutral pion photoproduction. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 679(1), 41-44. https://doi.org/10.1016/J.PHYSLETB.2009.07.0110370-2693https://doi.org/10.1016/j.physletb.2009.07.011https://hdl.handle.net/20.500.14468/24764This is an Accepted Manuscript of an article published by Elsevier in "Physics Letters B, Volume 679, Issue 1, 2009, Pages 41-44", available at: https://doi.org/10.1016/j.physletb.2009.07.011Este es el manuscrito aceptado del artículo publicado por Elsevier en "Physics Letters B, Volumen 679, Issue 1, 2009, Pag. 41-44", disponible en línea: https://doi.org/10.1016/j.physletb.2009.07.011The 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 O(q4), 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 E0+ 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.eninfo:eu-repo/semantics/openAccessartículopion photoproductionchiral perturbation theoryelectromagnetic multipoles