One loop contributions to neutral Higgs decay h-->mu tau

TL;DR

This paper compares numerical methods for calculating one-loop contributions to lepton-flavor violating Higgs decays, deriving preferable analytic expressions for models beyond the Standard Model and illustrating with a specific example.

Contribution

It provides a comparison of numerical and analytic approaches for one-loop calculations in LFV Higgs decays and identifies the most suitable expressions for extended models.

Findings

Analytic expressions can be effectively used alongside Looptools for calculations.

Preferred analytic formulas are identified for large parameter spaces in BSM models.

The approach is exemplified with a specific LFVHD process in a simple BSM model.

Abstract

In calculating one-loop contributions to amplitudes of the lepton-flavor violating decays of the neutral Higgses (LFVHD) to different flavor charged leptons, the analytic expressions can be written in term of Passarino-Veltman functions. Then, they can be computed numerically by Looptools [1]. Another approach is using suitable analytic expressions established for just this particular case. We compare numerical results obtained from Looptools and those computed by different expressions that have been applied recently. Then we derive the preferable ones that are applicable for the large ranges of free parameters introduced in the models beyond the Standard Model (SM). For illustration, the LFVHD in a simple model, which has been discussed recently, will be investigated more precisely.