Family symmetries and radiative corrections in multiscalar extensions of the Standard Model
Research output: Thesis › Doctoral Thesis (compilation)
Abstract
The four articles contained in this thesis all concern aspects of model building beyond the Standard Model (BSM). While Paper I mainly serves as a ``tool paper'' in which the results can be used to simplify certain calculations of oneloop effects from new heavy particles, Paper IIIV all deal with consequences of family symmetries in several BSM scenarios.
Paper I. We derive expressions for any number of derivatives of the ColemanWeinberg potential in a general renormalisable fourdimensional field theory with arbitrary number of fields with spin~$\leq$~1. These correspond to the oneloop contributions to scalar $n$point functions neglecting external momenta. The results are applied to two singlet extensions of the Standard Model, where we study the oneloop effects on the tripleHiggs coupling from the new exotic heavy states.
Paper II. In this paper we study a nonsupersymmetric trinification theory where a novel $\mathrm{SU}(3)_F$ family symmetry is imposed on the model. The treelevel scalar potential often has a global minimum where the trinification gauge group is broken to a LeftRight symmetric gauge group, and after integrating out all particles with masses of the order of the grand unification scale we show that the renormalisation group is able to trigger a radiative breaking down to the Standard Model gauge group with light Higgs doublets still remaining in the spectrum.
Paper III. This paper is about a supersymmetrised version of the $\mathrm{SU}(3)_F$ symmetric trinification model of Paper II. The absence of an appropriate scalar potential minimum is rectified by adding novel gauge adjoint chiral superfields. The resulting superpotential allows for a breaking of the grand unification symmetry, while all subsequent symmetry breaking scales are given by soft supersymmetry breaking parameters. The treelevel mass spectrum resulting from this soft breaking of supersymmetry is discussed.
Paper IV. A three Higgs doublet model is introduced with a $\mathrm{U}(1) \times \mathrm{U}(1)$ family symmetry that simultaneously enforces a Cabibbo quark mixing under charged current interactions and forbids treelevel flavour changing neutral currents. Furthermore, a hierarchy in the vacuum expectation values of the three doublets produces a SMlike Higgs boson and hierarchical fermion masses, and also causes the exotic scalar states to couple most strongly to the second quark family. A search strategy for the lightest charged scalar boson in the model is proposed that utilises the $c \bar{s}$ fusion channel, and is shown to be capable of probing a large portion of the model's parameter space. This is formulated in a model independent manner such that it can be directly applied to any model with the same discovery channel.
Paper I. We derive expressions for any number of derivatives of the ColemanWeinberg potential in a general renormalisable fourdimensional field theory with arbitrary number of fields with spin~$\leq$~1. These correspond to the oneloop contributions to scalar $n$point functions neglecting external momenta. The results are applied to two singlet extensions of the Standard Model, where we study the oneloop effects on the tripleHiggs coupling from the new exotic heavy states.
Paper II. In this paper we study a nonsupersymmetric trinification theory where a novel $\mathrm{SU}(3)_F$ family symmetry is imposed on the model. The treelevel scalar potential often has a global minimum where the trinification gauge group is broken to a LeftRight symmetric gauge group, and after integrating out all particles with masses of the order of the grand unification scale we show that the renormalisation group is able to trigger a radiative breaking down to the Standard Model gauge group with light Higgs doublets still remaining in the spectrum.
Paper III. This paper is about a supersymmetrised version of the $\mathrm{SU}(3)_F$ symmetric trinification model of Paper II. The absence of an appropriate scalar potential minimum is rectified by adding novel gauge adjoint chiral superfields. The resulting superpotential allows for a breaking of the grand unification symmetry, while all subsequent symmetry breaking scales are given by soft supersymmetry breaking parameters. The treelevel mass spectrum resulting from this soft breaking of supersymmetry is discussed.
Paper IV. A three Higgs doublet model is introduced with a $\mathrm{U}(1) \times \mathrm{U}(1)$ family symmetry that simultaneously enforces a Cabibbo quark mixing under charged current interactions and forbids treelevel flavour changing neutral currents. Furthermore, a hierarchy in the vacuum expectation values of the three doublets produces a SMlike Higgs boson and hierarchical fermion masses, and also causes the exotic scalar states to couple most strongly to the second quark family. A search strategy for the lightest charged scalar boson in the model is proposed that utilises the $c \bar{s}$ fusion channel, and is shown to be capable of probing a large portion of the model's parameter space. This is formulated in a model independent manner such that it can be directly applied to any model with the same discovery channel.
Details
Authors  

Organisations  
Research areas and keywords  Subject classification (UKÄ) – MANDATORY
Keywords

Original language  English 

Qualification  Doctor 
Awarding Institution  
Supervisors/Assistant supervisor 

Award date  2018 May 18 
Place of Publication  Lund 
Publisher 

Print ISBNs  9789177536710 
Electronic ISBNs  9789177536717 
Publication status  Published  2018 
Publication category  Research 
Bibliographic note
Defence details
Date: 20180518
Time: 13:00
Place: Hall K404, Department of Physics, Sölvegatan 14A, Lund
External reviewer(s)
Name: Porod, Werner
Title: Prof. Dr.
Affiliation: Theoretische Physik II, Universität Würzburg, Germany

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Related research output
CamargoMolina, J. E., Mandal, T., Roman Pasechnik & Wessén, J., 2018 Mar 1, In : Journal of High Energy Physics. 2018, 3, 24.
Research output: Contribution to journal › Article
CamargoMolina, J. E., Morais, A. P., Astrid Ordell, Roman Pasechnik, Sampaio, M. O. P. & Wessén, J., 2017 Apr 1, In : Physical Review D  Particles, Fields, Gravitation and Cosmology. 95, 7, 075031.
Research output: Contribution to journal › Article
CamargoMolina, J. E., Morais, A. P., Roman Pasechnik & Wessén, J., 2016 Sep 1, In : Journal of High Energy Physics. 2016, 9, 129.
Research output: Contribution to journal › Article