相关论文: Anomalies, U(1)' and the MSSM

We study an extension of the MSSM by an anomalous abelian vector multiplet and a St\"uckelberg multiplet. The anomalies are cancelled by the Green-Schwarz mechanism and the addition of Chern-Simons terms. The advantage of this choice over…

We study the collider phenomenology of a neutral gauge boson $Z'$ arising in minimal but anomalous $\mathrm{U}(1)$ extensions of the Standard Model (SM). To retain gauge invariance of physical observables, we consider cancellation of gauge…

We elaborate on an extension of the Standard Model with a gauge structure enlarged by a single anomalous U(1), where the presence of a Wess-Zumino term is motivated by the Green-Schwarz mechanism of string theory. The additional gauge…

The existence of the neutrino mass and flavor mixing have been experimentally verified. These phenomena strongly motivate to extend the Standard Model (SM). Amongst many possibilities, a simple and interesting extension of the SM can be…

Motivated by the apparent need for extending the MSSM and perhaps mitigating naturalness problems associated with the $\mu$ parameter and fine-tuning of the soft masses, we augment the MSSM spectrum by a SM gauge singlet chiral superfield,…

In this thesis we study the phenomenology of an anomalous U(1) extension of the MSSM. We briefly introduce the concept of Supersymmetry and describe the MSSM, then we introduce our extended model, describing its main properties. Then it…

We present a set of example models in which the Standard Model (SM) symmetry group is extended by a new abelian symmetry. This additional symmetry appears anomalous in the effective low-energy theory; however, the anomalies cancel out when…

We study the phenomenology of a $U_X(1)$ extension of the Standard Model where the SM particles are not charged under the new abelian group. The Green-Schwarz mechanism insures that the model is anomaly free. The erstwhile invisible dark…

We study a softly-broken supersymmetric model whose gauge symmetry is that of the standard model (SM) gauge group times an extra Abelian symmetry U(1)'. We call this gauge-extended model U(1)' model, and we study a U(1)' model with a…

We explore the anomaly-cancellation constraints on simplified dark matter (DM) models with an extra U(1)$^\prime$ gauge boson $Z'$. We show that, if the Standard Model (SM) fermions are supplemented by a single DM fermion $\chi$ that is a…

This thesis work analyzes basic field theoretical aspects of a class of models motivated by orientifold vacua of string theory and some of their phenomenological applications at the Large Hadron Collider. They extend the gauge structure of…

The measurement of the forward-backward asymmetry at LHC could be an important instrument to pinpoint the features of extra neutral gauge particles obtained by an extension of the gauge symmetry group of the standard model. For…

We consider a class of $U(1)^\prime$-extended MSSM in which the $U(1)^{\prime}$ symmetry is broken by vacuum expectation values (VEVs) of four MSSM singlet fields. While one MSSM singlet field interacts with the MSSM Higgs fields, three of…

We classify all the phenomenologically viable fermion mass matrices coming from a spontaneously broken abelian symmetry $ U(1)_X, $ with one and two additional chiral fields of opposite charges $ X=\pm 1. $ We find that the non-trivial…

We study a class of non-exotic minimal $U(1) '$ extensions of the Standard Model, which includes all scenarios that are anomaly-free with the ordinary fermion content augmented by one Right-Handed neutrino per generation, wherein the new…

An extension of the Standard Model by at least one extra U(1) gauge symmetry has been investigated by many authors. In this paper we explore the possibility that this extra U(1) is anomalous. One of the possible signatures of this model…

In the $\mu\nu$SSM, the presence of $R$-parity violating couplings involving right-handed (RH) neutrinos solves simultaneously the $\mu$- and $\nu$-problems. We explore extensions of the $\mu \nu$SSM adding a $U(1)'$ gauge group, which…

I suggest a minimal extension of the SM with $U(1)_{B-L}\otimes Z_{2}$. It can simultaneously accommodate the tiny neutrino mass, cold dark mater and baryon asymmetry besides the SM. All of the new physics arise from the $U(1)_{B-L}$…

We have studied the lightest masses in the fermionic sector of an anomalous $U(1)'$ extension of the Minimal Supersymmetric Standard Model (MSSM) inspired by brane constructions. The LSP of this model is an XWIMP (extremely weak interaction…

The concept of chirality is extended to the Minimal Supersymmetric Standard Model (MSSM) and the mu term is forbidden by a gauged U(1)' symmetry. R-parity automatically emerges after symmetry breaking, suppressing proton decay and…