Scotogenic $Z_2$ or $U(1)_D$ Model of Neutrino Mass with $\Delta(27)$   Symmetry
  The scotogenic model of radiative neutrino mass with $Z_2$ or $U(1)_D$ dark matter is shown to accommodate $\Delta(27)$ symmetry naturally. The resulting neutrino mass matrix is identical to either of two forms, one proposed in 2006, the other in 2008. These two structures are studied in the context of present neutrino data, with predictions of $CP$ violation and neutrinoless double beta decay. 
Ernest Ma and Alexander Natale (UC Riverside)
hep-ph