 Award ID(s):
 1813694
 NSFPAR ID:
 10173823
 Date Published:
 Journal Name:
 ArXivorg
 ISSN:
 23318422
 Page Range / eLocation ID:
 1  12
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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We present simple and predictive realizations of neutrino masses in theories based on the SU(6) grand unifying group. At the level of the lowestdimension operators, this class of models predicts a skewsymmetric flavor structure for the Dirac mass term of the neutrinos. In the case that neutrinos are Dirac particles, the lowestorder prediction of this construction is then one massless neutrino and two degenerate massive neutrinos. Higherdimensional operators suppressed by the Planck scale perturb this spectrum, allowing a good fit to the observed neutrino mass matrix. A firm prediction of this construction is an inverted neutrino mass spectrum with the lightest neutrino hierarchically lighter than the other two, so that the sum of neutrino masses lies close to the lower bound for an inverted hierarchy. In the alternate case that neutrinos are Majorana particles, the mass spectrum can be either normal or inverted. However, the lightest neutrino is once again hierarchically lighter than the other two, so that the sum of neutrino masses is predicted to lie close to the corresponding lower bound for the normal or inverted hierarchy. Near future cosmological measurements will be able to test the predictions of this scenario for the sum of neutrino masses. In the case of Majorana neutrinos that exhibit an inverted hierarchy, future neutrinoless double beta experiments can provide a complementary probe.more » « less

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