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Calculating the Two-photon Contribution to $\pi^0 \rightarrow e^+ e^-$ Decay Amplitude

High Energy Physics - Lattice 2020-01-17 v1

Abstract

We develop a new method that allows us to deal with two-photon intermediate states in a lattice QCD calculation. We apply this method to perform a first-principles calculation of the π0e+e\pi^0 \rightarrow e^+ e^- decay amplitude. Both the real and imaginary parts of amplitude are calculated. The imaginary part is compared with the prediction of optical theorem to demonstrate the effectiveness of this method. Our result for the real part of decay amplitude is 19.68(52)(1.10) eV19.68(52)(1.10) \ \text{eV}, where the first error is statistical and the second is systematic.

Keywords

Cite

@article{arxiv.2001.05642,
  title  = {Calculating the Two-photon Contribution to $\pi^0 \rightarrow e^+ e^-$ Decay Amplitude},
  author = {Norman H. Christ and Xu Feng and Luchang Jin and Cheng Tu and Yidi Zhao},
  journal= {arXiv preprint arXiv:2001.05642},
  year   = {2020}
}

Comments

7 pages, 4 figures, Proceedings of the 37th Annual International Symposium on Lattice Field Theory (Lattice 2019), 16-22 June 2019, Wuhan, China

R2 v1 2026-06-23T13:12:36.994Z