Horizontal gauge symmetry as a natural CP-violation source at the two-generation level

Aharon Davidson, Mehmet Koca, Kameshwar C. Wali

Research output: Contribution to journalArticle

17 Citations (Scopus)


We show that the classification of the WS-GIM generations by horizontal gauge symmetries can give rise to CP violation already at the two-generation level. The smallness of the CP-violation phase associated with the K0-K0 system is correlated with the smallness of the physical Cabibbo-like angle which emerges in the up-quark sector. We argue that strict lepton number conservation severely restricts the horizontal symmetries and requires a non-trivial vertical structure. The effective lowest-order four-fermion CP-violating operator is calculated in a recently proposed (SU(2) × U(1)) × U′ (1) model.

Original languageEnglish
Pages (from-to)47-51
Number of pages5
JournalPhysics Letters B
Issue number1
Publication statusPublished - Sep 10 1979


ASJC Scopus subject areas

  • Nuclear and High Energy Physics

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