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arXiv · 0810.4441

Universal extra dimension: Violation of Kaluza-Klein parity

Biplob Bhattacherjee
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Abstract

The minimal Universal Extra Dimension (mUED) model respects the Kaluza-Klein (KK) parity $(-1)^n$, where $n$ is the KK number. However, it is possible to have interactions located at only one of the two fixed points of the $S_1/\ztwo$ orbifold. Such asymmetric interactions violate the KK parity. This kills the cold dark matter component of UED but also removes the upper bound on the inverse compactification radius, and thus non-observation of the KK excitations even at the Large Hadron Collider does not necessarily invalidate the model. Apart from the decay of the lightest $n=1$ KK excitation, this leads to collider signals which are markedly different from those in the mUED scenario. The phenomenological consequences of such KK-parity violating terms are explored.

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Biplob Bhattacherjee. 2009-02-09. Universal extra dimension: Violation of Kaluza-Klein parity. https://doi.org/10.1103/physrevd.79.016006

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