Chargino contributions in light of recent ϵ′/ϵ

Recently, the standard model prediction of ϵ′/ϵ was improved, and a discrepancy from the experimental results was reported at the 2.9σ level. We study the chargino contributions to Z penguin especially with the vacuum stability constraint. The vacuum decay rate is investigated, and it is shown that the discrepancy can be explained if superparticles are lighter than 4-6 TeV. Correlations with B(KL→π0νν¯) and other experimental constraints are also discussed.