| 1. |
- Camargo-Molina, José Eliel, et al.
(författare)
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All one-loop scalar vertices in the effective potential approach
- 2016
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; 2016:8
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Tidskriftsartikel (refereegranskat)abstract
- Using the one-loop Coleman-Weinberg effective potential, we derive a general analytic expression for all the derivatives of the effective potential with respect to any number of classical scalar fields. The result is valid for a renormalisable theory in four dimensions with any number of scalars, fermions or gauge bosons. This result corresponds to the zero-external momentum contribution to a general one-loop diagram with N scalar external legs. We illustrate the use of the general result in two simple scalar singlet extensions of the Standard Model, to obtain the dominant contributions to the triple couplings of light scalar particles under the zero external momentum approximation.
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| 2. |
- Camargo-Molina, José Eliel, et al.
(författare)
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Charged scalars from SU(3)3 theories
- 2016
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Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 286
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Konferensbidrag (refereegranskat)abstract
- Inspired by a recently proposed GUT model based on the trinification (SU(3)3) gauge group with a global family (SU(3)F) symmetry, we consider an effective low-energy three Higgs doublet model that may shed light on what underlies the observed fermion mass hierarchies and CKM mixing. We discuss possibilities for charged scalars coming from this model to show in collider experiments and show some interesting benchmark points.
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| 3. |
- Camargo-Molina, José Eliel, et al.
(författare)
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Heavy charged scalars from cs̄ fusion : a generic search strategy applied to a 3HDM with U(1) x U(1) family symmetry
- 2018
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Ingår i: Journal of High Energy Physics (JHEP). - 1126-6708 .- 1029-8479. ; :3
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Tidskriftsartikel (refereegranskat)abstract
- We describe a class of three Higgs doublet models (3HDMs) with a softly broken U(1) x U(1) family symmetry that enforces a Cabibbo-like quark mixing while forbidding tree-level flavour changing neutral currents. The hierarchy in the observed quark masses is partly explained by a softer hierarchy in the vacuum expectation values of the three Higgs doublets. As a consequence, the physical scalar spectrum contains a Standard Model (SM) like Higgs boson h(125) while exotic scalars couple the strongest to the second quark family, leading to rather unconventional discovery channels that could be probed at the Large Hadron Collider. In particular, we describe a search strategy for the lightest charged Higgs boson H-+/-, through the process cs̄ -> H+ -> W+ h(125), using a multivariate analysis that leads to an excellent discriminatory power against the SM background. Although the analysis is applied to the proposed class of 3HDMs, we employ a model-independent formulation such that it can be applied to any other model with the same discovery channel.
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| 4. |
- Camargo-Molina, José Eliel, et al.
(författare)
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On a radiative origin of the Standard Model from trinification
- 2016
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Ingår i: Journal of High Energy Physics. - 1029-8479. ; 2016:9
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we present a trinification-based grand unified theory incorporating a global SU(3) family symmetry that after a spontaneous breaking leads to a left-right symmetric model. Already at the classical level, this model can accommodate the matter content and the quark Cabbibo mixing in the Standard Model (SM) with only one Yukawa coupling at the unification scale. Considering the minimal low-energy scenario with the least amount of light states, we show that the resulting effective theory enables dynamical breaking of its gauge group down to that of the SM by means of radiative corrections accounted for by the renormalisation group evolution at one loop. This result paves the way for a consistent explanation of the SM breaking scale and fermion mass hierarchies.
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| 5. |
- Camargo-Molina, José Eliel, et al.
(författare)
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On a radiative origin of the standard model in non-supersymmetric trinification with global SU(3)F
- 2016
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Ingår i: Proceedings of Science. - 1824-8039. ; Part F128560
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Tidskriftsartikel (refereegranskat)abstract
- We present a trinification-based grand unified theory incorporating a global SU(3)F family symmetry, that after spontaneous symmetry breaking leads to a left-right symmetric model. In addition to unification of gauge couplings, the model unifies Yukawa interactions and contains equivalent representations in the scalar and fermion sectors at high energy scales. Considering the minimal low-energy scenario with the least amount of light states, we show that the resulting effective theory enables dynamical breaking of its gauge group to that of the Standard Model by means of radiative corrections accounted for by the renormalisation group evolution at leading order. This result paves the way for a possible explanation of the SM breaking scale and fermion mass hierarchies.
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| 6. |
- Camargo-Molina, José E., et al.
(författare)
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Reviving trinification models through an E6 -extended supersymmetric GUT
- 2017
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Ingår i: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 2470-0010. ; 95:7
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Tidskriftsartikel (refereegranskat)abstract
- We present a supersymmetric (SUSY) model based on trinification [SU(3)]3 and family SU(3)F symmetries embedded into a maximal subgroup of E8, where the sectors of light Higgs bosons and leptons are unified into a single chiral supermultiplet. The common origin of gauge trinification and of the family symmetry from E8 separates the model from other trinification-based GUTs, as it protects, in particular, the Standard Model fermions from gaining mass until the electroweak symmetry is broken. Furthermore, it allows us to break the trinification symmetry via vacuum expectation values in SU(3)-adjoint scalars down to a left-right symmetric theory. Simultaneously, it ensures the unification of the gauge and Yukawa couplings as well as proton stability. Although the low-energy regime (e.g., mass hierarchies in the scalar sector determined by a soft SUSY-breaking mechanism) is yet to be established, these features are one key to revive the once very popular trinification-based GUTs.
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| 7. |
- Camargo-Molina, José E., et al.
(författare)
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Scale hierarchies, symmetry breaking, and particle spectra in SU(3)-family extended SUSY trinification
- 2019
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Ingår i: Physical Review D. - 2470-0010. ; 99:3
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Tidskriftsartikel (refereegranskat)abstract
- A unification of left-right SU(3)L×SU(3)R, color SU(3)C, and family SU(3)F symmetries in a maximal rank-8 subgroup of E8 is proposed as a landmark for future explorations beyond the Standard Model (SM). We discuss the implications of this scheme in a supersymmetric (SUSY) model based on the trinification gauge [SU(3)]3 and global SU(3)F-family symmetries. Among the key properties of this model are the unification of SM Higgs and lepton sectors, a common Yukawa coupling for chiral fermions, the absence of the μ problem, gauge couplings unification, and proton stability to all orders in perturbation theory. The minimal field content consistent with a SM-like effective theory at low energies is composed of one E6 27-plet per generation as well as three gauge and one family SU(3) octets inspired by the fundamental sector of E8. The details of the corresponding (SUSY and gauge) symmetry-breaking scheme, multiscale gauge couplings' evolution, and resulting effective low-energy scenarios are discussed.
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| 8. |
- Irbäck, Anders, et al.
(författare)
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Thermodynamics of amyloid formation and the role of intersheet interactions
- 2015
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Ingår i: Journal of Chemical Physics. - : AIP Publishing. - 0021-9606 .- 1089-7690. ; 143:10
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Tidskriftsartikel (refereegranskat)abstract
- The self-assembly of proteins into beta-sheet-rich amyloid fibrils has been observed to occur with sigmoidal kinetics, indicating that the system initially is trapped in a metastable state. Here, we use a minimal lattice-based model to explore the thermodynamic forces driving amyloid formation in a finite canonical (NVT) system. By means of generalized-ensemble Monte Carlo techniques and a semi-analytical method, the thermodynamic properties of this model are investigated for different sets of intersheet interaction parameters. When the interactions support lateral growth into multi-layered fibrillar structures, an evaporation/condensation transition is observed, between a supersaturated solution state and a thermodynamically distinct state where small and large fibril-like species exist in equilibrium. Intermediate-size aggregates are statistically suppressed. These properties do not hold if aggregate growth is one-dimensional. (C) 2015 AIP Publishing LLC.
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| 9. |
- Wessén, Jonas
(författare)
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Family symmetries and radiative corrections in multi-scalar extensions of the Standard Model
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)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 one-loop effects from new heavy particles, Paper II--IV all deal with consequences of family symmetries in several BSM scenarios. Paper I. We derive expressions for any number of derivatives of the Coleman-Weinberg potential in a general renormalisable four-dimensional field theory with arbitrary number of fields with spin~$\leq$~1. These correspond to the one-loop 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 one-loop effects on the triple-Higgs coupling from the new exotic heavy states. Paper II. In this paper we study a non-supersymmetric trinification theory where a novel $\mathrm{SU}(3)_F$ family symmetry is imposed on the model. The tree-level scalar potential often has a global minimum where the trinification gauge group is broken to a Left-Right 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 tree-level 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 tree-level flavour changing neutral currents. Furthermore, a hierarchy in the vacuum expectation values of the three doublets produces a SM-like 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.
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| 10. |
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