Cabibbofavored

Cabibbofavored, more commonly written as Cabibbo-favored (CF), refers to a classification of weak hadron decays in which the underlying quark-level transition proceeds through CKM matrix elements that are relatively large. In these decays the change in quark flavor involves the leading CKM factors, resulting in comparatively higher decay probabilities than more suppressed channels. CF decays are contrasted with Cabibbo-suppressed decays, which involve smaller CKM elements, and with doubly Cabibbo-suppressed decays that involve two small factors.

Origin and usage: The concept arises from Nicola Cabibbo’s description of quark mixing, later incorporated into the CKM framework by Kobayashi and Maskawa. The shorthand CF is widely used in experimental and theoretical particle physics to categorize decay channels and to organize measurements of branching fractions and CP-violation effects. While formal discussions often use the hyphenated term Cabibbo-favored, some texts and informal usages render it as Cabibbofavored or without a hyphen.

Examples: In charm physics, D0 decays to K- pi+ are considered Cabibbo-favored because they proceed via a c -> s transition with large CKM elements. In bottom meson decays, B0 -> D- pi+ is another CF process. By contrast, decays like D0 -> pi- pi+ or B0 -> pi+ pi- are typically described as Cabibbo-suppressed or, in some cases, doubly Cabibbo-suppressed depending on the quark-level path.

Significance: Classifying decays as CF helps predict relative rates and interpret weak interaction dynamics, though actual observed rates also depend on hadronic effects and kinematics. The framework extends across mesons and baryons and remains a practical tool in CKM-related analyses.