Complete one-loop matching of the type-I seesaw model onto the Standard Model effective field theory

Abstract

In this paper, we accomplish the complete one-loop matching of the type-I seesaw model onto the Standard Model Effective Field Theory (SMEFT), by integrating out three heavy Majorana neutrinos with the functional approach. It turns out that only 31 dimension-six operators (barring flavor structures and Hermitian conjugates) in the Warsaw basis of the SMEFT can be obtained, and most of them appear at the one-loop level. The Wilson coefficients of these 31 dimension-six operators are computed up to $$ \mathcal{O} $$ O (M−2) with M being the mass scale of heavy Majorana neutrinos. As the effects of heavy Majorana neutrinos are encoded in the Wilson coefficients of these higher-dimensional operators, a complete one-loop matching is useful to explore the low-energy phenomenological consequences of the type-I seesaw model. In addition, the threshold corrections to the couplings in the Standard Model and to the coefficient of the dimension-five operator are also discussed.

Effective comparison of neutrino-mass models

“…[29] for a general tree-level analysis). Our results [17] for the one-loop leading-log WCs in the type-I seesaw model was confirmed by the recent analysis [41], which actually performs the full one-loop matching for this model. Our result [17] for the one-loop finite WCs of the dipole operators in the type-I seesaw agrees with [42].…”

From models to SMEFT and back?

“…Generic expressions for the low-energy effective action of a gauge theory at the one-loop order were derived in the 80s [36]. More recently, the approach has been further explored, particularly within the context of SMEFT [37][38][39][40][41][42][43][44][45][46][47][48][49][50].…”

Snowmass White Paper: Effective Field Theory Matching and Applications

“…type-I, -II and -III neutrino seesaw models [40][41][42], as well as a survey of 16 different single scalar extensions of the Standard Model [43].…”