New physics in ϵ′ from gluomagnetic contributions and limits on Left-Right symmetry

New physics in the chromomagnetic flavor changing transition s ! dg0 can avoid the strong Glashow- Iliopoulos-Maiani suppression of the standard model and lead to large contributions to CP-violating observables, in particular to the 0 parameter, that we address here. We discuss the case of the left-right symmetric models, where this contribution implies bounds on the phases of the right-handed quark mixing matrix, or in generic models with large phases a strong bound on the left-right symmetry scale. To the leading order, a numeric formula for 0 as a function of the short-distance coefficients for a wide class of models of new physics is given.

New physics in the chromomagnetic flavor changing transition s→dg∗ can avoid the strong Glashow-Iliopoulos-Maiani suppression of the standard model and lead to large contributions to CP-violating observables, in particular to the ϵ′ parameter, that we address here. We discuss the case of the left-right symmetric models, where this contribution implies bounds on the phases of the right-handed quark mixing matrix, or in generic models with large phases a strong bound on the left-right symmetry scale. To the leading order, a numeric formula for ϵ′ as a function of the short-distance coefficients for a wide class of models of new physics is given.