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arXiv · hep-ph/0307365

Flavor Hierarchy from Extra Dimension and Gauge Threshold Correction

Kiwoon Choi·Ian-Woo Kim·Wan Young Song
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Abstract

Dynamical quasi-localization of matter fields in extra dimension is an elegant mechanism to generate hierarchical 4-dimensional Yukawa couplings. We point out that a bulk matter field whose zero mode is quasi-localized can give a large Kaluza-Klein threshold correction to low energy gauge couplings, which is generically of the order of ln (Yukawa)/8pi^2, so it can significantly affect gauge coupling unification. We compute such threshold corrections in generic 5-dimensional theories compactified on S^1/Z_2 X Z_2, and apply the result to grand unified theories on orbifold generating small Yukawa couplings through quasi-localization.

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Kiwoon Choi, Ian-Woo Kim, Wan Young Song. 2003-08-06. Flavor Hierarchy from Extra Dimension and Gauge Threshold Correction. https://doi.org/10.1016/j.nuclphysb.2004.03.018

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