Improved Standard-Model prediction for ${\pi }^0\to e^{+}{e}^{-}$

Abstract

We present an improved Standard-Model (SM) prediction for the dilepton decay of the neutral pion. The loop amplitude is determined by the pion transition form factor for ${\pi }^0\to {\gamma }^{\ast }{\gamma }^{\ast }$, for which we employ a dispersive representation that incorporates both space-like and time-like data as well as short-distance constraints. The resulting SM branching fraction, $\text{BR}[{\pi }^0\to e^{+}{e}^{-}]=6.25(3)\times 10^{-8}$ , sharpens constraints on physics beyond the SM, including pseudoscalar and axial-vector mediators.

9 pages, 3 figures; journal version

References in corpus (23)

• Measurement of the fine-structure constant as a test of the Standard Model
• Collider Probes of Axion-Like Particles
• Measurement of gamma gamma* --> pi0 transition form factor at Belle
• Towards a data-driven analysis of hadronic light-by-light scattering
• Compilation of low-energy constraints on 4-fermion operators in the SMEFT
• Lattice QCD at the physical point: light quark masses
• Light Cone Sum Rules for the pi0-gamma*-gamma Form Factor Revisited
• Dispersive analysis of the pion transition form factor
• Measurement of the rare decay pi0 -> e+ e-
• On the transition form factors of the axial-vector resonance $f_1(1285)$ and its decay into $e^{+}{e}^{-}$
• A dispersive estimate of scalar contributions to hadronic light-by-light scattering
• Rare decay pi0 -> e+e-: theory confronts KTeV data
• Asymptotic behavior of meson transition form factors
• First-Generation New Physics in Simplified Models: From Low-Energy Parity Violation to the LHC
• Rare decay ${\pi }^0\to e^{+}{e}^{-}$: on corrections beyond the leading order
• Measurement of the ${\pi }^0$ electromagnetic transition form factor slope
• Determination of the Parity of the Neutral Pion via the Four-Electron Decay
• Measurement of the pi^0 -> e^+e^-gamma Dalitz decay at the Mainz Microtron
• Dispersion representations and anomalous singularities of the triangle diagram
• Complete structure dependent analysis of the decay $P\to l^{+}{l}^{-}$
• QED radiative corrections to the decay pi^0 to e^+e^-
• On mass corrections to the decays P \to l^+l^-
• On the two-photon contributions to $e^{+}{e}^{-}\to \eta \gamma$ and $e^{+}{e}^{-}\to {\eta }^{\prime }\gamma$

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• Flavor probes of axion-like particles
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• Dispersion relation for hadronic light-by-light scattering: subleading contributions
• Dispersion relation for hadronic light-by-light scattering: $\eta$ and ${\eta }^{\prime }$ poles
• An updated view on the ATOMKI nuclear anomalies
• Lattice QCD calculation of ${\pi }^0\to e^{+}{e}^{-}$ decay
• Complete dispersive evaluation of the hadronic light-by-light contribution to muon $g-2$
• Precision evaluation of the $\eta$- and ${\eta }^{\prime }$-pole contributions to hadronic light-by-light scattering in the anomalous magnetic moment of the muon
• The semileptonic decays ${\eta }^{(\prime )}\to {\pi }^0{\ell }^{+}{\ell }^{-}$ and ${\eta }^{\prime }\to \eta {\ell }^{+}{\ell }^{-}$ in the standard model
• Improved Standard-Model prediction for $K_L\to {\ell }^{+}{\ell }^{-}$
• Hadronic light-by-light scattering in the anomalous magnetic moments of electron and $\tau$
• Workshop summary -- Kaons@CERN 2023
• Neutral-pion decay into an electron-positron pair: A review and update