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K+ -> pi+ nu nu(bar) and FCNC from non-universal Z' bosons

Xiao-Gang He·G. Valencia
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Abstract

Motivated by the E787 and E949 result for K+ -> pi+ nu nu(bar) we examine the effects of a new non-universal right-handed Z' boson on flavor changing processes. We place bounds on the tree-level FCNC from K-K(bar) and B-B(bar) mixing as well as from the observed CP violation in kaon decay. We discuss the implications for K -> pi nu nu(bar), B -> X nu nu(bar) and B -> tau+ tau-. We find that existing bounds allow substantial enhancements in the K+ -> pi+ nu nu(bar) rate, particularly through a new one-loop Z' penguin operator.

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Xiao-Gang He, G. Valencia. 2004-09-03. K+ -> pi+ nu nu(bar) and FCNC from non-universal Z' bosons. https://doi.org/10.1103/physrevd.70.053003

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