CP violating hW(+)W(-) coupling in the Standard Model and beyond

• Autor(a) principal: Huang, Da
• Data de Publicação: 2021
• Outros Autores: Morais, António P., Santos, Rui
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.21/13268
• topic: Beyond Standard Model; CP violation

Inspired by the recent development in determining the property of the observed Higgs boson, we explore the CP-violating (CPV) -cCPVhW+mu nu W</mml:mover>mu nu-/upsilon coupling in the Standard Model (SM) and beyond, where W-+/- mu nu and W</mml:mover>+/- mu nu denote the W-boson field strength and its dual. To begin with, we show that the leading-order SM contribution to this CPV vertex appears at two-loop level. By summing over the quark flavor indices in the two loop integrals analytically, we can estimate the order of the corresponding Wilson coefficient to be cCPVSM<mml:mo>similar to O<mml:mfenced close=")" open="(">10<mml:mo>-23</mml:mfenced>, which is obviously too small to be probed at the LHC and planned future colliders. Then we investigate this CPV hW(+)W(-) interaction in two Beyond the Standard Model benchmark models: the left-right model and the complex 2-Higgs doublet model (C2HDM). Unlike what happens for the SM, the dominant contributions in both models arise at the one-loop level, and the corresponding Wilson coefficient can be as large as of O(10(-9)) in the former model and of O(10(-3)) for the latter. In light of such a large CPV effect in the hW(+)W(-) coupling, we also give the formulae for the leading one-loop contribution to the related CPV hZZ effective operator in the complex 2-Higgs doublet model. The order of magnitude of the Wilson coefficients in the C2HDM may be within reach of the high-luminosity LHC or planned future colliders.