Classification of effective operators for interactions between the Standard Model and dark matter

Understand

We construct a basis for effective operators responsible for interactions between the Standard Model and a dark sector composed of particles with spin less or equal to 1.

• Redundant operators are eliminated using dim-4 equations of motion.
• We consider simple scenarios where the dark matter components are stabilized against decay by Z2 symmetries.
• We determine operators which are loop-generated within an underlying theory and those that are potentially tree-level generated.