Updated Standard Model Prediction for ${\epsilon }^{\prime }/\epsilon$

Abstract

A recent lattice evaluation of ${\epsilon }^{\prime }/\epsilon$, finding a 2.1 $\sigma$ deviation from the experimental value, has revived the old debate about a possible ${\epsilon }^{\prime }/\epsilon$ anomaly. The unfounded claims of a too low Standard Model prediction are based on incorrect estimates that neglect the long-distance re-scattering of the final pions in $K\to 2\pi$. In view of the current situation, we have recently updated the Standard Model calculation, including all known short- and long-distance contributions. Our result, $\text{Re}\left({\epsilon }^{\prime }/\epsilon \right)=(15\pm 7)\cdot 10^{-4}$, is in complete agreement with the experimental measurement.

arXiv comment8 pages, 3 figures, talk given at 21th International Conference in Quantum Chromodynamics (QCD 18), 2 - 6 July 2018, Montpellier - FR

References in corpus (42)

• Weak Decays Beyond Leading Logarithms
• Kaon Decays in the Standard Model
• The Anatomy of ${\epsilon }^{\prime }/\epsilon$ Beyond Leading Logarithms with Improved Hadronic Matrix Elements
• Towards a consistent estimate of the chiral low-energy constants
• Mesonic low-energy constants
• Standard-model prediction for direct CP violation in $K\to \pi \pi$ decay
• Precise Measurements of Direct CP Violation, CPT Symmetry, and Other Parameters in the Neutral Kaon System
• Right-handed charged currents in the era of the Large Hadron Collider
• The < S P P > Green function and SU(3) breaking in K_{l3} decays
• Patterns of Flavour Violation in Models with Vector-Like Quarks
• Quark flavour observables in the Littlest Higgs model with T-parity after LHC Run 1
• Improved anatomy of epsilon'/epsilon in the Standard Model
• Isospin violation in epsilon'
• The Standard Model Prediction for epsilon'/epsilon
• The $K\to (\pi \pi {)}_{I=2}$ Decay Amplitude from Lattice QCD
• Weak $K$--Amplitudes in the Chiral and $1/N_c$--Expansions
• Yukawa enhancement of $Z$-mediated New Physics in $\Delta S=2$ and $\Delta B=2$ Processes
• Lattice determination of the $K\to (\pi \pi {)}_{I=2}$ Decay Amplitude $A_2$
• An ${\epsilon }^{\prime }$ improvement from right-handed currents
• Standard Model Confronting New Results for epsilon'/epsilon
• Supersymmetric Explanation of CP Violation in $K\to \pi \pi$ Decays
• Colourless Mesons in a Polychromatic World
• Revisiting Kaon Physics in General $Z$ Scenario
• Emerging understanding of the ΔI = 1/2 Rule from Lattice QCD
• The $\Delta I=1/2$ Rule in the Chiral Limit
• Master formula for ${\epsilon }^{\prime }/\epsilon$ beyond the Standard Model
• Chargino contributions in light of recent ${\epsilon }^{\prime }/\epsilon$
• Singularity-free Next-to-leading Order $\Delta S=1$ Renormalization Group Evolution and ${\epsilon }_K^{\prime }/{\epsilon }_K$ in the Standard Model and Beyond
• Determination of the Chiral Couplings L_10 and C_87 from Semileptonic Tau Decays
• ${\epsilon }^{\prime }/\epsilon$ from charged-Higgs-induced gluonic dipole operators
• Towards a determination of the chiral couplings at NLO in 1/N(C): L_8(mu) and C_38(mu)
• QCD corrections to inclusive $\Delta S=1,2$ transitions at the next-to-leading order
• The vector form factor at the next-to-leading order in 1/N(C): chiral couplings L9(mu) and C88(mu) - C90(mu)
• An updated analysis of eps'/eps in the standard model with hadronic matrix elements from the chiral quark model
• Updated determination of chiral couplings and vacuum condensates from hadronic tau decay data
• Dispersion relations and soft pion theorems for K -> pi pi
• Reanalysis of pion pion phase shifts from K -> pi pi decays
• 331 Models Facing the Tensions in $\Delta F=2$ Processes with the Impact on ${\epsilon }^{\prime }/\epsilon$, $B_s\to {\mu }^{+}{\mu }^{-}$ and $B\to K^{\ast }{\mu }^{+}{\mu }^{-}$
• Probing SUSY effects in $K_S^0\to {\mu }^{+}{\mu }^{-}$
• ${\epsilon }_K$ and ${\epsilon }^{\prime }/\epsilon$ in a diquark model
• Recent progress in applying lattice QCD to kaon physics
• Delta I=1/2 Rule, epsilon'/epsilon and K -> pi nu nubar in Z'(Z) and G' Models with FCNC Quark Couplings

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