Johan Rathsman
Senior lecturer
ℤ 2 breaking effects in 2-loop RG evolution of 2HDM
Author
Summary, in English
We investigate the effects of a ℤ
2
symmetry in the CP-conserving Two-Higgs-Doublet-Model (2HDM); which is often imposed to prevent Flavor-Changing-Neutral-Currents (FCNCs) at tree-level. Specifically, we analyze how a breaking of the ℤ
2
symmetry spreads during renormalization group evolution; employing general 2-loop renormalization group equations that we have derived. Evolving the model from the electroweak to the Planck scale, we find that while the case of an exact ℤ
2
symmetric 2HDM is very constrained, a soft breaking of the ℤ
2
symmetry extends the valid parameter space regions. The effects of a hard ℤ
2
breaking in the scalar sector as well as the stability of the flavor alignment ansatz are also investigated. We find that while a hard breaking of the ℤ
2
symmetry in the potential is problematic, since it speeds up the growth of quartic couplings, the generated FCNCs are heavily suppressed. Conversely, we also find that hard ℤ
2
breaking in the Yukawa sector at most gives moderate ℤ
2
breaking in the potential; whereas the FCNCs can become quite sizable far away from the ℤ
2
symmetric regions.
Department/s
- Theoretical Particle Physics - Has been reorganised
Publishing year
2019-02-22
Language
English
Publication/Series
Journal of High Energy Physics
Volume
2019
Issue
2
Document type
Journal article
Publisher
Springer
Topic
- Subatomic Physics
Keywords
- Beyond Standard Model
- Higgs Physics
Status
Published
ISBN/ISSN/Other
- ISSN: 1029-8479