A realistic formulation of approximate CP
Abstract
CP violation in the SM is naturally implemented as a small imaginary perturbation to real Yukawa couplings. For example, a large CP asymmetry in B_d decays can arise if the imaginary parts of quark mass matrices are of order 10^(-3)m_t,b or smaller. Applying the same principle of ``additive CP violation'' to soft SUSY-breaking terms, the electric dipole moments of the neutron and mercury atom are predicted near current experimental limits; for nonuniversal A-terms, EDM bounds can be satisfied given certain flavour structures. The proposal is conveniently formulated in a democratic basis, with Yukawas and soft terms of the form const. x (1+eps+i zeta) where eps<<1, zeta<~10^(-3), motivated by approximate permutation x CP symmetry.
Cite
@article{arxiv.hep-ph/0206086,
title = {A realistic formulation of approximate CP},
author = {Thomas Dent and Joaquim Silva-Marcos},
journal= {arXiv preprint arXiv:hep-ph/0206086},
year = {2010}
}
Comments
28 pages, 2 tables v3: improved notation and discussion of 'removability' v2: revised discussion of USY, improved notation of SUSY section, added acknowledgements and references