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arXiv · 1711.07526

Radiative corrections to masses and couplings in Universal Extra Dimensions

Ayres Freitas·Kyoungchul Kong·Daniel Wiegand
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Abstract

Models with an orbifolded universal extra dimension receive important loop-induced corrections to the masses and couplings of Kaluza-Klein (KK) particles. The dominant contributions stem from so-called boundary terms which violate KK number. Previously, only the parts of these boundary terms proportional to $\ln(ΛR)$ have been computed, where $R$ is the radius of the extra dimension and $Λ$ is cut-off scale. However, for typical values of $ΛR \sim 10 \cdots 50$, the logarithms are not particularly large and non-logarithmic contributions may be numerically important. In this paper, these remaining finite terms are computed and their phenomenological impact is discussed. It is shown that the finite terms have a significant impact on the KK mass spectrum. Furthermore, one finds new KK-number violating interactions that do not depend on $\ln(ΛR)$ but nevertheless are non-zero. These lead to new production and decay channels for level-2 KK particles at colliders.

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Ayres Freitas, Kyoungchul Kong, Daniel Wiegand. 2018-02-26. Radiative corrections to masses and couplings in Universal Extra Dimensions. https://doi.org/10.1007/jhep03(2018)093

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