A short look at epsilon'/epsilon

Abstract

We analyze the theoretical implications of the new KTeV measurement of direct CP-violation in K->pi pi decays. The result is found consistent with the Standard Model for low values of the strange quark mass m_s. If the hadronic parameters B_6^{(1/2)} and B_8^{(3/2)} satisfy 2 B_6^{(1/2)} - B_8^{(3/2)} < 2, as suggested by lattice and 1/N_c calculations, we find an upper bound of 110 MeV for m_s (2 GeV)$. We parametrize potential new physics contributions to ε'/εand illustrate their correlation with upper bounds on m_s. Finally we discuss a non-perturbative mechanism, which is not contained in the existing calculations of B_6^{(1/2)}. This mechanism enhances B_6^{(1/2)} and thereby leads to a better understanding of the Delta I=1/2 rule and the high measured value of Re (ε^\prime/ε)

typo in eq. (5) corrected, 2 refs. added, some clarifications in text, keywords/PACS-no. added

References in corpus (2)

• Supersymmetric contributions to rare kaon decays: beyond the single mass-insertion approximation
• Lattice B-parameters for $\Delta S=2$ and $\Delta I=3/2$ Operators

Cited by in corpus (26)

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• Final State Interactions in Kaon Decays
• Analysis of ε'/εin the 1/N_c Expansion
• epsilon'/epsilon at the NLO: 10 Years Later
• B->rho pi decays, resonant and nonresonant contributions
• New QCD estimate of the kaon penguin matrix elements and epsilon'/epsilon
• An updated analysis of eps'/eps in the standard model with hadronic matrix elements from the chiral quark model
• Large Delta(I)=3/2 Contribution to epsilon'/epsilon in Supersymmetry
• Fully supersymmetric CP violations in the kaon system
• Supersymmetric contributions to direct CP violation in K -> pi pi gamma decays
• Combined analysis of the unitarity triangle and CP violation in the Standard Model
• Final State Interactions and epsilon'/epsilon: A Critical Look
• Gluino-squark contributions to CP violations in the kaon system
• Theoretical status of epsilon'/epsilon
• Comments on CP, T and CPT Violation in Neutral Kaon Decays
• Constraints on the Mass and Mixing of the 4th Generation Quark From Direct CP Violation${\epsilon }^{\prime }/\epsilon$ and Rare K Decays
• Nonstandard order parameters and the origin of CP violation
• V-A hadronic tau decays : a QCD laboratory
• Ruling out the Weinberg Model of Spontaneous CP Violation
• Theoretical status of epsilon'/epsilon
• Penguins diagrams in Delta I=1/2 rule and ε'/εwith σmodels
• Chargino contributions to ${\epsilon }^{\prime }/\epsilon$ in the left-right supersymmetric model
• A priori mixing of mesons and the |Delta I|=1/2 rule in K\toππ