Testable two-loop radiative neutrino mass model based on an $LLQd^cQd^c$ effective operator

Understand

A new two-loop radiative Majorana neutrino mass model is constructed from the gauge-invariant effective operator $L^i L^j Q^k d^c Q^l d^c \epsilon_{ik} \epsilon_{jl}$ that violates lepton number conservation by two units.

• The ultraviolet completion features two scalar leptoquark flavors and a color-octet Majorana fermion.
• We show that there exists a region of parameter space where the neutrino oscillation data can be fitted while simultaneously meeting flavor-violation and collider bounds.
• The model is testable through lepton flavor-violating processes such as ${\mu} \to e{\gamma}$, $\mu \to eee$, and $\mu N \to eN$ conversion, as well as collider searches for the scalar leptoquarks and color-octet fermion.