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arXiv · hep-ph/0107298

See-saw mechanism and four light neutrino state

M. Czakon·J. Gluza·M. Zralek
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Abstract

A formal proof is given that in a see-saw type neutrino mass matrix with only two neutrino mass scales ($m_D \ll m_R$) and the maximal rank of $m_{R(D)}$, we can not get a fourth light sterile neutrino.

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M. Czakon, J. Gluza, M. Zralek. 2001-07-30. See-saw mechanism and four light neutrino state. https://doi.org/10.1103/physrevd.64.117304

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