Radiative left-right Dirac neutrino mass

We consider the conventional left-right gauge extension of the standard model of quarks and leptons without a scalar bidoublet. We study systematically how one-loop radiative Dirac neutrino masses may be obtained. In addition to two well-known cases from almost 30 years ago, we find two new scenarios with verifiable predictions. (C) 2017 The Author(s). Published by Elsevier B.V.