Strong Isospin Breaking in CP - even and CP - odd K → ππ Decays
نویسنده
چکیده
Complete next-to-leading (chiral) order (NLO) expressions for the strong isospin-breaking (IB) contributions in K → ππ are used to discuss (1) for CP-even, the impact on the magnitude of the ∆I = 1/2 Rule, and (2) for CP-odd, the strong IB correction, Ωst, for the gluonic penguin contribution to ǫ /ǫ, with particular emphasis on the strong low-energy constant (LEC) and loop contributions, numerical values for which are model-independent at NLO. In the presence of IB, the standard isospin decomposition of the K → ππ, K → ππ, ππ decay amplitudes, A+0, A+− and A00, becomes [1]
منابع مشابه
Effects in CP - even and CP - odd K → ππ Decays
Strong isospin-breaking (IB) effects in CP-even and CP-odd K → ππ decays are computed to next-to-leading order (NLO) in the chiral expansion. The impact of these corrections on the magnitude of the ∆I = 1/2 Rule and on the size of the IB correction, ΩIB, to the gluonic penguin contribution to ǫ /ǫ are discussed. In the presence of IB, the standard isospin decomposition of the K → ππ, K → ππ, ππ...
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