Non-minimal flavor-violation in the MSSM

The MSSM possesses many new sources of flavor violation. In addition to the minimally flavor-violating interactions involving the CKM matrix there are terms which have a priori a generic flavor structure (including possible complex phases) stemming from the supersymmetry-breaking sector. Especially, the trilinear A-terms can have an important effect on flavor-violating observables because they are both chirality and flavor violating. In the presence of generic sources of flavor-violation processes mediated by squarks and gluinos are of special interest because they involve the strong coupling constant. This would lead to dangerously large effects, which would be in contradiction with experiment if the flavor structure were arbitrary. The difficulty to explain why the soft-supersymmetry breaking terms are approximately universal, or aligned to the quark sector, is known as the "SUSY flavor problem".