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Enhanced Gluino Box Contribution to epsilon'/epsilon in SUSY

Matthias Neubert
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Abstract

We show that in supersymmetric extensions of the Standard Model gluino box diagrams can yield a large CP-violating Delta(I)=3/2 contribution to s->d+q(bar)+q flavor-changing neutral current processes, which feeds into the I=2 isospin amplitude in K->pi+pi decays. This contribution only requires moderate mass splitting between the right-handed squarks u(tilde)_R and d(tilde)_R, 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 naturally be an order of magnitude larger than the measured value.

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Matthias Neubert. 2000-11-04. Enhanced Gluino Box Contribution to epsilon'/epsilon in SUSY. https://doi.org/10.1142/s0217751x01007777

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