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arXiv · 1812.08473

Seesaw model with hidden $SU(2)_H \times U(1)_X$ gauge symmetry

Takaaki Nomura·Hiroshi Okada
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Abstract

We propose a seesaw model with a hidden gauge symmetry $SU(2)_H \times U(1)_X$ where two types of standard model singlet fermions in realizing a seesaw mechanism are organized into $SU(2)_H$ doublet. Then we formulate scalar and gauge sector, neutrino mass matrix and lepton flavor violations. In our gauge sector, $Z$-$Z'$ mixing appears after spontaneous symmetry breaking and we investigate constraint from $\rho$-parameter. In addition we discuss $Z'$ production at the large hadron collider via $Z$-$Z'$ mixing, where $Z'$ tends to dominantly decay into heavy neutrinos.

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Takaaki Nomura, Hiroshi Okada. 2018-12-20. Seesaw model with hidden $SU(2)_H \times U(1)_X$ gauge symmetry. https://doi.org/10.1103/physrevd.100.115011

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