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arXiv · 1706.05268

A model with isospin doublet $U(1)_D$ gauge symmetry

Takaaki Nomura·Hiroshi Okada
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Abstract

We propose a model with an extra isospin doublet $U(1)_D$ gauge symmetry, in which we introduce several extra fermions with odd parity under a discrete $Z_2$ symmetry in order to cancel the gauge anomalies out. A remarkable issue is that we impose nonzero $U(1)_D$ charge to the standard model Higgs, and it gives the most stringent constraint to the vacuum expectation value of a scalar field breaking the $U(1)_D$ symmetry that are severer than the LEP bound. We then explore relic density of a Majorana dark matter candidate without conflict of constraints from lepton flavor violating processes. A global analysis is carried out to search for parameters which can accommodate with observed data.

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Takaaki Nomura, Hiroshi Okada. 2017-06-15. A model with isospin doublet $U(1)_D$ gauge symmetry. https://doi.org/10.1142/s0217751x18500896

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