Naturalness of nearly degenerate neutrinos

Nuclear Physics B

Volumn 556, Issue 1-2, 1999, Pages 3-22

  Casas, J A ^a,b   Espinosa, J R ^b   Ibarra, A ^a   Navarro, I ^a  

^a INSTITUTO DE ESTRUCTURA DE LA MATERIA   (Spain)

^b CERN   (Switzerland)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0033530058     PISSN: 05503213     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0550-3213(99)00383-1     Document Type: Article

References (57)

1. Y. Fukuda et al., Super-Kamiokande Collaboration, Phys. Lett. B 433 (1998) 9; Phys. Rev. Lett. 81 (1998) 1562; S. Hatakeyama et al., Kamiokande Collaboration, Phys. Rev. Lett. 81 (1998) 2016; M. Ambrosio et al., MACRO Collaboration, Phys. Lett. B 434 (1998) 451.
2. Y. Fukuda et al., Super-Kamiokande Collaboration, Phys. Lett. B 433 (1998) 9; Phys. Rev. Lett. 81 (1998) 1562; S. Hatakeyama et al., Kamiokande Collaboration, Phys. Rev. Lett. 81 (1998) 2016; M. Ambrosio et al., MACRO Collaboration, Phys. Lett. B 434 (1998) 451.
3. Y. Fukuda et al., Super-Kamiokande Collaboration, Phys. Lett. B 433 (1998) 9; Phys. Rev. Lett. 81 (1998) 1562; S. Hatakeyama et al., Kamiokande Collaboration, Phys. Rev. Lett. 81 (1998) 2016; M. Ambrosio et al., MACRO Collaboration, Phys. Lett. B 434 (1998) 451.
4. Y. Fukuda et al., Super-Kamiokande Collaboration, Phys. Lett. B 433 (1998) 9; Phys. Rev. Lett. 81 (1998) 1562; S. Hatakeyama et al., Kamiokande Collaboration, Phys. Rev. Lett. 81 (1998) 2016; M. Ambrosio et al., MACRO Collaboration, Phys. Lett. B 434 (1998) 451.
5. H. Georgi and S.L. Glashow, hep-ph/9808293.
6. F. Vissani, hep-ph/9708483; V. Barger, S. Pakvasa, T.J. Weiler and K. Whisnant, Phys. Lett. B 437 (1998) 107.
7. F. Vissani, hep-ph/9708483; V. Barger, S. Pakvasa, T.J. Weiler and K. Whisnant, Phys. Lett. B 437 (1998) 107.
8. C. Giunti, Phys. Rev. D 59 (1999) 077301.
9. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
10. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
11. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
12. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
13. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
14. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
15. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
16. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
17. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
18. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
19. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
20. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
21. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
22. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
23. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
24. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
25. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
26. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
27. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
28. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
29. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
30. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
31. C.D. Carone, M. Sher, Phys. Lett. B 420 (1998) 83; A.S. Joshipura, Z. Phys. C 64 (1994) 31; A. Ioannisian and J.W.F. Valle, Phys. Lett. B 332 (1994) 93; D. Caldwell and R.N. Mohapatra, Phys. Rev. D 48 (1993) 3259; G.K. Leontaris, S. Lola, C. Scheich and J.D. Vergados, Phys. Rev. D 53 (1996) 6381; S. Lola and J.D. Vergados, Prog. Part. Nucl. Phys. 40 (98) 71; B.C. Allanach, Phys. Lett. B 450 (1999) 182; A.J. Baltz, A.S. Goldhaber and M. Goldhaber, Phys. Rev. Lett. 81 (1998) 5730; R.N. Mohapatra and S. Nussinov, Phys. Lett. B 441 (1998) 299; Phys. Rev. D 60 (1999) 013002; C. Jarlskog, M. Matsuda and S. Skadhauge, Phys. Lett. B 449 (1999) 240; Y. Nomura and T. Yanagida, Phys. Rev. D 59 (1999) 017303; S.K. Rang and C.S. Kim, Phys. Rev. D 59 (1999) 091302; S. Davidson and S. King, Phys. Lett. B 445 (1998) 191; H. Fritzsch and Z. Xing, Phys. Lett. B 440 (1998) 313; hep-ph/9903499; M. Tanimoto, Phys. Rev. D 59 (1998) 017304; N. Haba, Phys. Rev. D 59 (1999) 035011; Yue-Liang Wu, hep-ph/9901245; E. Ma, Phys. Lett. B 456 (1999) 48; hep-ph/9902465; E.M. Lipmanov, hep-ph/9901316; T. Ohlsson and H. Snellman, hep-ph/9903252; A.H. Guth, L. Randall and M. Serna, hep-ph/9903464; G.C. Branco, M.N. Rebelo and J.I. Silva-Marcos, Phys. Rev. Lett. 82 (1999) 683.
32. R. Barbieri et al., JHEP 9812 (1998) 017; G.L. Fogli, E. Lisi, A. Marrone and G. Scioscia, Phys. Rev. D 59 (1999) 033001, hep-ph/9904465.
33. R. Barbieri et al., JHEP 9812 (1998) 017; G.L. Fogli, E. Lisi, A. Marrone and G. Scioscia, Phys. Rev. D 59 (1999) 033001, hep-ph/9904465.
34. Y. Fukuda et al., Super-Kamiokande Collaboration, Phys. Rev. Lett. 82 (1999) 1810.
35. D. Casper and E. Kearns, private communications.
36. L. Baudis et al., Heidelberg-Moscow exp., Phys. Rev. Lett. 83 (1999) 41.
37. V. Lobashev, Pontecorvo Prize Lecture at the JINR, Dubna, January 1999; A.I. Belesev et al., Phys. Lett. B 350 (1995) 263.
38. V. Lobashev, Pontecorvo Prize Lecture at the JINR, Dubna, January 1999; A.I. Belesev et al., Phys. Lett. B 350 (1995) 263.
39. See e.g. F. Vissani, hep-ph/9904349.
40. Y.L. Wu, hep-ph/9810491; hep-ph/9901245; hep-ph/9901320; C. Wetterich, Phys. Lett. B 451(1999) 397; R. Barbieri, L.J. Hall, G.L. Kane and G.G. Ross, hep-ph/9901228.
41. Y.L. Wu, hep-ph/9810491; hep-ph/9901245; hep-ph/9901320; C. Wetterich, Phys. Lett. B 451(1999) 397; R. Barbieri, L.J. Hall, G.L. Kane and G.G. Ross, hep-ph/9901228.
42. Y.L. Wu, hep-ph/9810491; hep-ph/9901245; hep-ph/9901320; C. Wetterich, Phys. Lett. B 451(1999) 397; R. Barbieri, L.J. Hall, G.L. Kane and G.G. Ross, hep-ph/9901228.
43. G. Altarelli and F. Feruglio, Phys. Lett. B 439 (1998) 112, JHEP 9811 (1998) 021; Phys. Lett. B 451(1999) 388.
44. G. Altarelli and F. Feruglio, Phys. Lett. B 439 (1998) 112, JHEP 9811 (1998) 021; Phys. Lett. B 451(1999) 388.
45. G. Altarelli and F. Feruglio, Phys. Lett. B 439 (1998) 112, JHEP 9811 (1998) 021; Phys. Lett. B 451(1999) 388.
46. S. Weinberg, Phys. Rev. Lett. 43 (1979) 1566.
47. K. Babu, C.N. Leung and J. Pantaleone, Phys. Lett. B 319 (1993) 191.
48. M. Gell-Mann, P. Ramond and R. Slansky, Proc. Supergravity Stony Brook Workshop, New York, 1979, ed. P. Van Nieuwenhuizen and D. Freedman (North-Holland, Amsterdam); T. Yanagida, Proc. Workshop on Unified Theories and Baryon Number in the Universe, Tsukuba, Japan 1979 (ed. A. Sawada, A. Sugamoto, KEK Report No. 79-18, Tsukuba); R. Mohapatra and G. Senjanovič, Phys. Rev. Lett. 44 (1980) 912; Phys. Rev. D 23 (1981) 165.
49. M. Gell-Mann, P. Ramond and R. Slansky, Proc. Supergravity Stony Brook Workshop, New York, 1979, ed. P. Van Nieuwenhuizen and D. Freedman (North-Holland, Amsterdam); T. Yanagida, Proc. Workshop on Unified Theories and Baryon Number in the Universe, Tsukuba, Japan 1979 (ed. A. Sawada, A. Sugamoto, KEK Report No. 79-18, Tsukuba); R. Mohapatra and G. Senjanovič, Phys. Rev. Lett. 44 (1980) 912; Phys. Rev. D 23 (1981) 165.
50. M. Gell-Mann, P. Ramond and R. Slansky, Proc. Supergravity Stony Brook Workshop, New York, 1979, ed. P. Van Nieuwenhuizen and D. Freedman (North-Holland, Amsterdam); T. Yanagida, Proc. Workshop on Unified Theories and Baryon Number in the Universe, Tsukuba, Japan 1979 (ed. A. Sawada, A. Sugamoto, KEK Report No. 79-18, Tsukuba); R. Mohapatra and G. Senjanovič, Phys. Rev. Lett. 44 (1980) 912; Phys. Rev. D 23 (1981) 165.
51. M. Gell-Mann, P. Ramond and R. Slansky, Proc. Supergravity Stony Brook Workshop, New York, 1979, ed. P. Van Nieuwenhuizen and D. Freedman (North-Holland, Amsterdam); T. Yanagida, Proc. Workshop on Unified Theories and Baryon Number in the Universe, Tsukuba, Japan 1979 (ed. A. Sawada, A. Sugamoto, KEK Report No. 79-18, Tsukuba); R. Mohapatra and G. Senjanovič, Phys. Rev. Lett. 44 (1980) 912; Phys. Rev. D 23 (1981) 165.
52. B. Grzadkowski and M. Lindner, Phys. Lett. B 193 (1987) 71; Yu.F. Pirogov and O.V. Zenin, hep-ph/9808396; N. Haba, Y. Matsui, N. Okamura and M. Sugiura, hep-ph/9810471; hep-ph/9904292.
53. B. Grzadkowski and M. Lindner, Phys. Lett. B 193 (1987) 71; Yu.F. Pirogov and O.V. Zenin, hep-ph/9808396; N. Haba, Y. Matsui, N. Okamura and M. Sugiura, hep-ph/9810471; hep-ph/9904292.
54. B. Grzadkowski and M. Lindner, Phys. Lett. B 193 (1987) 71; Yu.F. Pirogov and O.V. Zenin, hep-ph/9808396; N. Haba, Y. Matsui, N. Okamura and M. Sugiura, hep-ph/9810471; hep-ph/9904292.
55. J.A. Casas, V. Di Clemente, A. Ibarra and M. Quirós, hep-ph/9904295.
56. A. De Rújula, M.B. Gavela and P. Hernández, Nucl. Phys. B 547 (1999) 21.
57. J. Ellis and S. Lola, hep-ph/9904279.