What can we learn from the total width of the Higgs boson?

TL;DR

The paper explores how the total width of the Higgs boson varies across different new physics models, highlighting its potential as a probe for physics beyond the Standard Model.

Contribution

It provides a comparative analysis of Higgs width modifications in various new physics scenarios, including scalar extensions and composite models.

Findings

Higgs width is generally smaller than the Standard Model prediction in many models.

Enhanced Yukawa couplings can significantly increase the Higgs width.

Precision measurements at the high-luminosity LHC can distinguish between models.

Abstract

As one of the key properties of the Higgs boson, the Higgs total width is sensitive to global profile of the Higgs boson couplings, and thus new physics would modify the Higgs width. We investigate the total width in various new physics models, including various scalar extension, composite Higgs models, and fraternal twin Higgs model. Typically the Higgs width is smaller than the standard model value due to mixture with other scalar if the Higgs is elementary, or curved Higgs field space for the composite Higgs. On the other hand, except the possible invisible decay mode, the enhanced Yukawa coupling in the two Higgs doublet model or the exotic fermion embeddings in the composite Higgs, could enhance the Higgs width greatly. The precision measurement of the Higgs total width at the high-luminosity LHC can be used to discriminate certain new physics models.