R-parity ($R_p$)

R-parity is the multiplicative quantum number $R_p=(-1{)}^{3(B-L)+2s}$. Standard Model particles are even and their superpartners are odd.

R-parity violation permits interactions containing an odd number of superpartners. Renormalizable R-parity-violating interactions can violate lepton number or baryon number, and allowing both generically induces rapid proton decay.