Sum Rule Constraint on Models Beyond the Standard Model

TL;DR

This paper derives a sum rule constraint on Yukawa couplings in BSM models using W boson mass and LHC data, enabling tests and exclusions of many theories as experimental precision improves.

Contribution

It introduces a sum rule relating Yukawa couplings across different scalar doublets in BSM models, providing a new way to test these theories against experimental data.

Findings

Sum rule constrains Yukawa couplings in BSM models.

LHC data can test and potentially exclude BSM theories.

Improved accuracy will refine constraints on new physics.

Abstract

In most versions of beyond the standard model (BSM) physics, the Yukawa couplings of the quarks and charged leptons are not all to the same complex scalar doublet but to different ones. Comparison to the standard model (SM) with only one scalar doublet, using the known mass of the W boson, provides a sum rule constraint on the Yukawa couplings $Y_i,~~ i=t, b, \tau,.....$ of the form $\Sigma_i r_i^2 = 1$ where $r_i = Y_i^{(SM)}/Y_i^{(BSM)}$ and the sum is over distinct scalar doublets. The LHC data on the branching ratios $H \rightarrow \gamma\gamma, ~\bar{b}b, ~\tau^+\tau^-, ~etc.,$ allows detailed comparison to this sum rule constraint and, as accuracy improves, will constrain or exclude many BSM theories.