scholarly journals A Review of the Exceptional Supersymmetric Standard Model

Symmetry ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 557
Author(s):  
Stephen F. King ◽  
Stefano Moretti ◽  
Roman Nevzorov
Keyword(s):  
Gauge Symmetry ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Hadron Collider ◽  
Gauge Coupling ◽  
Higgs Bosons ◽  
Anomaly Cancellation ◽  
Flavor Changing ◽  
Low Energies ◽  
The Right

Local supersymmetry (SUSY) provides an attractive framework for the incorporation of gravity and unification of gauge interactions within Grand Unified Theories (GUTs). Its breakdown can lead to a variety of models with softly broken SUSY at low energies. In this review article, we focus on the SUSY extension of the Standard Model (SM) with an extra U ( 1 ) N gauge symmetry originating from a string-inspired E 6 GUTs. Only in this U ( 1 ) extension of the minimal supersymmetric standard model (MSSM) can the right-handed neutrinos be superheavy, providing a mechanism for the baryon asymmetry generation. The particle content of this exceptional supersymmetric standard model (E 6 SSM) includes three 27 representations of the E 6 group, to ensure anomaly cancellation. In addition it also contains a pair of S U ( 2 ) W doublets as required for the unification of gauge couplings. Thus, E 6 SSM involves exotic matter beyond the MSSM. We consider symmetries that permit suppressing flavor changing processes and rapid proton decay, as well as gauge coupling unification, the gauge symmetry breaking and the spectrum of Higgs bosons in this model. The possible Large Hadron Collider (LHC) signatures caused by the presence of exotic states are also discussed.

scholarly journals E6 inspired SUSY models with custodial symmetry

2018 ◽  
Vol 33 (31) ◽  
pp. 1844007 ◽  
Author(s):  
R. Nevzorov
Keyword(s):  
Gauge Symmetry ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Exotic States ◽  
Grand Unified Theories ◽  
The Standard Model ◽  
Unified Theories ◽  
Low Energies ◽  
Custodial Symmetry ◽  
Susy Models

The breakdown of [Formula: see text] within the supersymmetric (SUSY) Grand Unified Theories (GUTs) can result in SUSY extensions of the standard model (SM) based on the SM gauge group together with extra [Formula: see text] gauge symmetry under which right-handed neutrinos have zero charge. In these [Formula: see text] extensions of the minimal supersymmetric standard model (MSSM) a single discrete [Formula: see text] symmetry may be used to suppress the most dangerous operators, that give rise to proton decay as well as nondiagonal flavour transitions at low energies. The SUSY models under consideration involves [Formula: see text] and extra exotic matter beyond the MSSM. We discuss leptogenesis within this SUSY model and argue that the extra exotic states may lead to the nonstandard Higgs decays.

scholarly journals Improved (g − 2)μ measurement and singlino dark matter in μ-term extended ℤ3-NMSSM

2021 ◽  
Vol 2021 (9) ◽  
Author(s):  
Junjie Cao ◽  
Jingwei Lian ◽  
Yusi Pan ◽  
Di Zhang ◽  
Pengxuan Zhu
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Hadron Collider ◽  
Higgs Bosons ◽  
Mass Hierarchy ◽  
Relic Abundance

Abstract Very recently, a Fermilab report of muon g− 2 showed a 4.2σ discrepancy between it and the standard model (SM) prediction. Motivated by this inspiring result and the increasing tension in supersymmetric interpretation of the anomalous magnetic moment, it is argued that in the general next-to-minimal supersymmetric standard model (GNMSSM), a singlino-dominated neutralino can act as a feasible dark matter (DM) candidate in explaining the discrepancy naturally. In this case, the singlino-dominated DM and singlet-dominated Higgs bosons can form a secluded DM sector with $$ {\overset{\sim }{\chi}}_1^0{\overset{\sim }{\chi}}_1^0 $$ χ ~ 1 0 χ ~ 1 0 → hsAs responsible for the measured DM relic abundance when $$ {m}_{{\overset{\sim }{\chi}}_1^0} $$ m χ ~ 1 0 ≳ 150 GeV and the Yukawa coupling κ is around 0.2. This sector communicates with the SM sector by weak singlet-doublet Higgs mixing, so the scatterings of the singlino-dominated DM with nucleons are suppressed. Furthermore, due to the singlet nature of the DM and the complex mass hierarchy, sparticle decay chains in the GNMSSM are lengthened in comparison with the prediction of the minimal supersymmetric standard model. These characteristics lead to sparticle detection at the Large Hadron Collider (LHC) being rather tricky. This study surveys a specific scenario of the GNMSSM, which extends the ℤ3-NMSSM by adding an explicit μ-term, to reveal the features. It indicates that the theory can readily explain the discrepancy of the muon anomalous magnetic moment without conflicting with the experimental results in DM and Higgs physics, and the LHC searches for sparticles.

scholarly journals Two Higgs Bosons near 125 GeV in the Complex NMSSM and the LHC Run I Data

2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Stefano Moretti ◽  
Shoaib Munir
Keyword(s):  
Higgs Boson ◽  
Large Hadron Collider ◽  
Cp Violation ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Hadron Collider ◽  
Higgs Sector ◽  
Higgs Bosons ◽  
Neutral Higgs Boson ◽  
The Impact

We analyse the impact of explicit CP-violation in the Higgs sector of the Next-to-Minimal Supersymmetric Standard Model (NMSSM) on its consistency with the Higgs boson data from the Large Hadron Collider (LHC). Through detailed scans of the parameter space of the complex NMSSM for certain fixed values of one of its CP-violating (CPV) phases, we obtain a large number of points corresponding to five phenomenologically relevant scenarios containing ∼125 GeV Higgs boson(s). We focus, in particular, on the scenarios where the visible peaks in the experimental samples can actually be explained by two nearly mass-degenerate neutral Higgs boson states. We find that some points corresponding to these scenarios give an overall slightly improved fit to the data, more so for nonzero values of the CPV phase, compared to the scenarios containing a single Higgs boson near 125 GeV.

scholarly journals E6 GUT and Baryon Asymmetry Generation in the E6CHM

Universe ◽  
2022 ◽  
Vol 8 (1) ◽  
pp. 33
Author(s):  
Roman Nevzorov
Keyword(s):  
Gauge Group ◽  
Top Quark ◽  
Gauge Coupling ◽  
Baryon Number ◽  
Higgs Doublet ◽  
Anomaly Cancellation ◽  
Strongly Coupled ◽  
Weakly Coupled ◽  
Low Energies ◽  
The Right

Grand unified theories (GUTs) may result in the E6-inspired composite Higgs model (E6CHM) at low energies, almost stabilizing the electroweak scale. We consider an orbifold GUT in 6 dimensions in which the E6-gauge group is broken to the gauge symmetry of the standard model (SM) while different multiplets of the SM fermions come from different 27-plets. The strongly coupled sector of the E6CHM is confined on the brane where E6 is broken down to its SU(6) subgroup. Near the scale of f≳5TeV, this approximate SU(6) symmetry is expected to be further broken down to its SU(5) subgroup, which contains the SM-gauge group. Such a breakdown leads to a set of pseudo-Nambu–Goldstone bosons (pNGBs) that includes an SM-like Higgs doublet. The approximate gauge coupling unification in the E6CHM takes place at high energies when the right-handed top quark is a composite fermion. To ensure anomaly cancellation, the weakly coupled sector of this model contains extra exotic matter beyond the SM. We discuss the mechanism of the generation of matter–antimatter asymmetry within the variant of the E6CHM in which the baryon number and CP invariance are violated.

scholarly journals ANOMALOUS U(1)A AND ELECTROWEAK SYMMETRY BREAKING

2001 ◽  
Vol 16 (13) ◽  
pp. 835-844
Author(s):  
ILIA GOGOLADZE ◽  
MIRIAN TSULAIA
Keyword(s):  
Gauge Symmetry ◽  
Standard Model ◽  
Symmetry Breaking ◽  
Supersymmetric Standard Model ◽  
Electroweak Symmetry Breaking ◽  
Electroweak Symmetry ◽  
Superstring Theory

We suggest a new mechanism for electroweak symmetry breaking in the supersymmetric Standard Model. Our suggestion is based on the presence of an anomalous U (1)A gauge symmetry, which naturally arises in the four-dimensional superstring theory, and heavily relies on the value of the corresponding Fayet–Illiopoulos ξ-term.

scholarly journals R-PARITY VIOLATING U(1)′-EXTENDED SUPERSYMMETRIC STANDARD MODEL

2008 ◽  
Vol 23 (39) ◽  
pp. 3271-3283 ◽  
Author(s):  
HYE-SUNG LEE
Keyword(s):  
Dark Matter ◽  
Gauge Symmetry ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Discrete Symmetries ◽  
Discrete Symmetry ◽  
New Physics ◽  
Dark Matter Candidate ◽  
Hidden Sector

Supersymmetry is one of the best motivated new physics scenarios. To build a realistic supersymmetric standard model, however, a companion symmetry is necessary to address various issues. While R-parity is a popular candidate that can address the proton and dark matter issues simultaneously, it is not the only option for such a property. We review how a TeV scale U(1)′ gauge symmetry can replace the R-parity. Discrete symmetries of the U(1)′ can make the model still viable and attractive with distinguishable phenomenology. For instance, with a residual discrete symmetry of the U(1)′, Z6 = B3 × U2, the proton can be protected by the baryon triality (B3) and a hidden sector dark matter candidate can be protected by the U-parity (U2).

scholarly journals Future prospects for the minimal supersymmetric standard model

2021 ◽  
pp. 2150188
Author(s):  
Shehu AbdusSalam ◽  
Safura S. Barzani ◽  
Mohammadreza Noormandipour
Keyword(s):  
Dark Matter ◽  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Cold Dark Matter ◽  
Direct Detection ◽  
Hadron Collider ◽  
Hadron Colliders ◽  
Future Prospects ◽  
Lower Limits

Experimental collaborations for the large hadron collider conducted various searches for supersymmetry. In the absence of signals, lower limits were put on sparticle masses but usually within frameworks with (over-)simplifications relative to the entire indications by supersymmetry models. For complementing current interpretations of experimental bounds, we introduce a 30-parameter version of the R-parity conserving Minimal Supersymmetric Standard Model (MSSM-30). Using a sample of the MSSM-30 which are in harmony with cold dark matter, flavor and precision electroweak constraints, we explicitly show the prospects for assessing neutralino candidate dark matter in contrast to future searches for supersymmetry. The MSSM-30-parameter regions that are beyond reach to dark matter direct detection experiments could be probed by future hadron–hadron colliders.

scholarly journals PREDICTIONS FOR $B \to \tau \bar{\mu} + \mu \bar{\tau}$

2013 ◽  
Vol 28 (31) ◽  
pp. 1350153 ◽  
Author(s):  
DRIS BOUBAA ◽  
ALAKABHA DATTA ◽  
MURUGESWARAN DURAISAMY ◽  
SHAABAN KHALIL
Keyword(s):  
Standard Model ◽  
Supersymmetric Standard Model ◽  
Minimal Supersymmetric Standard Model ◽  
Neutral Current ◽  
Higgs Sector ◽  
New Physics ◽  
Flavor Changing ◽  
Clear Sign ◽  
Flavor Changing Neutral Current ◽  
Extended Higgs Sector

The observation of [Formula: see text] at present experiments would be a clear sign of new physics. In this paper, we calculate this process in an extended Higgs sector framework where the decay is mediated by the exchange of spin zero particle with flavor changing neutral current couplings. If we identify the scalar with the newly discovered state at LHC with a mass ~125 GeV then we find that, after imposing all experimental constraints, the [Formula: see text] can be as high as ~10-6 and [Formula: see text] can be as high as ~10-7. We also calculate this process in the minimal supersymmetric standard model and find the [Formula: see text] is typically of the order ~10-8.

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