• CP-Violation in the \(ZZZ\) and \(ZWW\) vertices at \(e^+e^-\) colliders in Two-Higgs-Doublet Models 

      Grzadkowski, Bohdan; Øgreid, Odd Magne; Osland, Per (Peer reviewed; Journal article, 2016-05)
      We discuss possibilities of measuring CP violation in the Two-Higgs-Doublet Model by studying effects of one-loop generated \(ZZZ\) and \(ZWW\) vertices. We discuss a set of CP-sensitive asymmetries for \(ZZ\) and \(W^+W^-\) ...
    • Diagnosing CP properties of the 2HDM 

      Grzadkowski, Bohdan; Øgreid, Odd Magne; Osland, Per (Peer reviewed; Journal article, 2014-01)
      We have investigated a Two-Higgs-Doublet Model (2HDM), focusing on CP violation. Various scenarios with spontaneous and explicit breaking of CP have been considered. Some features of CP violation related to a choice of the ...
    • Heavy Higgs boson decays in the alignment limit of the 2HDM 

      Øgreid, Odd Magne; Osland, Per; Grzadkowski, Bohdan; Haber, Howard (Peer reviewed; Journal article, 2018-12)
      The Standard Model (SM)-like couplings of the observed Higgs boson impose strong constraints on the structure of any extended Higgs sector. We consider the theoretical properties and the phenomenological implications of a ...
    • Measuring CP violation in two-Higgs-doublet models in light of the LHC Higgs data 

      Grzadkowski, Bohdan; Øgreid, Odd Magne; Osland, Per (Peer reviewed; Journal article, 2014-11)
      In Two-Higgs-Doublet models, the conditions for CP violation can be ex- pressed in terms of invariants under U(2) rotations among the two SU(2) Higgs doublet fields. In order to design a strategy for measuring the invariants ...
    • A simple method to detect spontaneous CP violation in multi-Higgs models 

      Øgreid, Odd Magne; Osland, Per; Rebelo, Margarida N. (Peer reviewed; Journal article, 2017-08)
      For models with several Higgs doublets we present an alternative method to the one proposed by Branco, Gerard and Grimus, in 1984, to check whether or not CP is spontaneously violated in the Higgs potential. The previous ...
    • Spontaneous symmetry breaking in the S3-symmetric scalar sector 

      Emmanuel-Costa, David; Øgreid, Odd Magne; Osland, Per; Rebelo, Margarida N. (Peer reviewed; Journal article, 2016-02)
      We present a detailed study of the vacua of the S3-symmetric three-Higgs-doublet potential, specifying the region of parameters where these minimisation solutions occur. We work with a CP conserving scalar potential and ...
    • Symmetries and mass degeneracies in the scalar sector 

      Haber, Howard E.; Øgreid, Odd Magne; Osland, Per; Rebelo, Margarida N. (Peer reviewed; Journal article, 2019-01-04)
      We explore some aspects of models with two and three SU(2) scalar doublets that lead to mass degeneracies among some of the physical scalars. In Higgs sectors with two scalar doublets, the exact degeneracy of scalar masses, ...