2020 Impact factor 4.590
Particles and Fields
Eur. Phys. J. C 12, 507-520
DOI 10.1007/s100529900262

Neutrino masses, mixing angles and the unification
of couplings in the MSSM

M. Carena1 - J. Ellis1 - S. Lola1 - C.E.M. Wagner1,2

1 Theory Division, CERN, 1211 Geneva, Switzerland
2 Argonne National Laboratory, 9700 Cass Ave., Argonne, IL 60439, USA

Received: 22 June 1999 / Published online: 10 December 1999

In the light of the gathering evidence for $\nu_{\mu}-\nu_{\tau}$neutrino oscillations, coming in particular from the Super-Kamiokande data on atmospheric neutrinos, we re-analyze the unification of gauge and Yukawa couplings within the minimal supersymmetric extension of the Standard Model (MSSM). Guided by a range of different grand-unified models, we stress the relevance of large mixing in the lepton sector for the question of bottom-tau Yukawa coupling unification. We also discuss the dependence of the favoured value of $\tan\beta$ on the characteristics of the high-energy quark and lepton mass matrices. In particular, we find that, in the presence of large lepton mixing, Yukawa unification can be achieved for intermediate values of $\tan\beta$ that were previously disfavoured. The renormalization-group sensitivity to the structures of different mass matrices may enable Yukawa unification to serve as a useful probe of GUT models.

Copyright Springer-Verlag 2000