2010/03/26 by Ivica Picek, Picek, Ivica, Branimir Radovcic +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #hep-ph
paper · pdf · doi:10.48550/arxiv.1003.5100
Talk at BUE-CTP International Conference on Neutrino Physics in the LHC Era, Luxor, Egipt, November 2009.
arxiv created 2010/03/26 · arxiv updated 2010/03/29
We consider a scenario in which additional vectorlike TeV-scale fermions belonging to higher weak-isospin multiplets provide new seesaw mediators. If these fermions have non-zero hypercharge, their tree-level exchange produces novel seesaw mechanism different from type I and III seesaw. In order to produce Majorana masses for light neutrinos, new Dirac seesaw mediators are constrained by the SM gauge symmetry to belong to a weak triplet and a five-plet. The latter, in conjunction with two isospin 3/2 scalar multiplets, leads to new seesaw formula mν~ v6/M5. It reproduces the empirical masses mν~ 10-1 eV by M < TeV new states, testable at the LHC.