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ℤ 2 breaking effects in 2-loop RG evolution of 2HDM

Oredsson, Joel LU and Rathsman, Johan LU (2019) In Journal of High Energy Physics 2019(2).
Abstract


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... (More)


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.

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author
and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Beyond Standard Model, Higgs Physics
in
Journal of High Energy Physics
volume
2019
issue
2
article number
152
publisher
Springer
external identifiers
  • scopus:85062464027
ISSN
1029-8479
DOI
10.1007/JHEP02(2019)152
language
English
LU publication?
yes
id
97404f8a-c903-4e71-865a-eaf6663a3666
date added to LUP
2019-03-13 12:43:33
date last changed
2025-10-14 12:22:40
@article{97404f8a-c903-4e71-865a-eaf6663a3666,
  abstract     = {{<p><br>
                                                         We investigate the effects of a ℤ                             <br>
                            <sub>2</sub><br>
                                                          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                             <br>
                            <sub>2</sub><br>
                                                          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                             <br>
                            <sub>2</sub><br>
                                                          symmetric 2HDM is very constrained, a soft breaking of the ℤ                             <br>
                            <sub>2</sub><br>
                                                          symmetry extends the valid parameter space regions. The effects of a hard ℤ                             <br>
                            <sub>2</sub><br>
                                                          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                             <br>
                            <sub>2</sub><br>
                                                          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                             <br>
                            <sub>2</sub><br>
                                                          breaking in the Yukawa sector at most gives moderate ℤ                             <br>
                            <sub>2</sub><br>
                                                          breaking in the potential; whereas the FCNCs can become quite sizable far away from the ℤ                             <br>
                            <sub>2</sub><br>
                                                          symmetric regions.                         <br>
                        </p>}},
  author       = {{Oredsson, Joel and Rathsman, Johan}},
  issn         = {{1029-8479}},
  keywords     = {{Beyond Standard Model; Higgs Physics}},
  language     = {{eng}},
  month        = {{02}},
  number       = {{2}},
  publisher    = {{Springer}},
  series       = {{Journal of High Energy Physics}},
  title        = {{ℤ                         
                        <sub>2</sub>
                                                  breaking effects in 2-loop RG evolution of 2HDM}},
  url          = {{http://dx.doi.org/10.1007/JHEP02(2019)152}},
  doi          = {{10.1007/JHEP02(2019)152}},
  volume       = {{2019}},
  year         = {{2019}},
}