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arXiv · hep-ph/0107190

Fermion Mass Hierarchy in the Grand Unified Theory on $S_1/(Z_2 \times Z_2')$ Orbifold

N. Haba·Y. Shimizu·Tomoharu Suzuki·Kazumasa Ukai
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Abstract

We suggest a simple grand unified theory where the fifth dimensional coordinate is compactified on an $S_1/(Z_2 \times Z_2')$ orbifold. This model is based on the supersymmetric flipped $SU(5) \times U(1)$ grand unified theory, which can realize not only the triplet-doublet splitting but also the natural fermion mass hierarchies. The triplet-doublet splitting is realized by $S_1/(Z_2 \times Z_2')$ orbifolding, which also reduces the gauge group as $SU(5) \times U(1) \to SU(3)_c \times SU(2)_L \times U(1)_Z \times U(1)_X$. The suitable fermion mass hierarchies are generated by integrating out extra three sets of vector-like heavy fields which can propagate in five dimensions. The radiative corrections to the large Yukawa coupling of right-handed neutrinos can reduce the gauge group to $SU(3)_c \times SU(2)_L \times U(1)_Y$.

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N. Haba, Y. Shimizu, Tomoharu Suzuki, Kazumasa Ukai. 2001-10-23. Fermion Mass Hierarchy in the Grand Unified Theory on $S_1/(Z_2 \times Z_2')$ Orbifold. https://doi.org/10.1143/ptp.107.151

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