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Journal of High Energy Physics

, 2011:122 | Cite as

Two-loop QED radiative corrections to the decay π 0 → e + e : the virtual corrections and soft-photon bremsstrahlung

  • Petr Vaško
  • Jiří Novotný
Article

Abstract

This paper is devoted to the two-loop QED radiative corrections to the decay π 0 → e + e . We compute the virtual corrections without using any approximation and we take into account all the relevant graphs with the inclusion of those omitted in the previous approximative calculations. The bremsstrahlung is then treated within the soft photon approximation. We concentrate on the technical aspects of the calculation and discuss in detail the UV renormalization and the treatment of IR divergences within the dimensional regularization. As a result we obtain the O(α 3 p 2) contribution in closed analytic form. We compare the exact two-loop results with existing approximative calculations of QED corrections and find significant disagreement in the kinematical region relevant for the KTeV experiment.

Keywords

NLO Computations Chiral Lagrangians 

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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  1. 1.Institute of Particle and Nuclear Physics, Faculty of Mathematics and PhysicsCharles UniversityPrague 8Czech Republic

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