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Large Delta(I)=3/2 Contribution to epsilon'/epsilon in Supersymmetry

Alexander L. Kagan·Matthias Neubert
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Abstract

We show that in supersymmetric extensions of the Standard Model gluino box diagrams can yield a large Delta(I)=3/2 contribution to s->d+q(bar)+q FCNC processes, which may induce a sizable CP-violating contribution to the I=2 isospin amplitude in K->pi+pi decays. This contribution only requires moderate mass splitting between the right-handed up- and down-squarks, and persists for squark masses of order 1 TeV. Taking into account current bounds on Im(delta_{sd}^{LL}) from K-K(bar) mixing, the resulting contribution to epsilon'/epsilon could be an order of magnitude larger than the measured value.

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Alexander L. Kagan, Matthias Neubert. 1999-08-18. Large Delta(I)=3/2 Contribution to epsilon'/epsilon in Supersymmetry. https://doi.org/10.1103/physrevlett.83.4929

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