One-Loop Matching Conditions in Neutrino Effective Theory

TL;DR

This paper derives one-loop matching conditions for neutrino effective theories using a diagrammatic approach, clarifying threshold corrections when integrating out heavy right-handed neutrinos in the type I seesaw mechanism.

Contribution

It provides a detailed derivation of one-loop matching conditions for neutrino effective theories, complementing previous functional approach results.

Findings

Derived explicit one-loop matching conditions.

Quantified threshold corrections to parameters.

Validated results against existing functional methods.

Abstract

We investigate matching conditions and threshold corrections between full and effective theories based on the type I seesaw mechanism. In general, using an intuitive Feynman diagrammatical approach, we compute the amplitudes before and after integrating out heavy right-handed neutrinos at the matching scale. In particular, we derive the one-loop matching conditions between the full and the effective theories. The matching conditions of the parameters are influenced by one-loop corrections to the corresponding vertices as well as wave function corrections for the Higgs and the lepton fields. Our results are comparable to earlier results based on a functional approach.