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arXiv · 1005.0628

Revisiting Constraints on Fourth Generation Neutrino Masses

Linda M. Carpenter·Arvind Rajaraman
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Abstract

We revisit the current experimental bounds on fourth-generation Majorana neutrino masses, including the effects of right handed neutrinos. Current bounds from LEPII are significantly altered by a global analysis. We show that the current bounds on fourth generation neutrinos decaying to eW and mu W can be reduced to about 80 GeV (from the current bound of 90 GeV), while a neutrino decaying to tau W can be as light as 62.1 GeV. The weakened bound opens up a neutrino decay channel for intermediate mass Higgs, and interesting multi-particle final states for Higgs and fourth generation lepton decays.

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Linda M. Carpenter, Arvind Rajaraman. 2010-05-04. Revisiting Constraints on Fourth Generation Neutrino Masses. https://doi.org/10.1103/physrevd.82.114019

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