Related papers: Anomalous $U(1)'$ and Dark Matter
We identify the parameter regions of the phenomenological minimal supersymmetric standard model (pMSSM) with the minimal possible fine-tuning. We show that the fine-tuning of the pMSSM is not large, nor under pressure by LHC searches. Low…
In a model with an extra $U(1)$ gauge to SM gauge group, we have shown the allowed region of masses of extra gauge boson and the dark matter which is the lightest one among other right-handed Majorana fermions present in the model. To…
The Weakly Interacting Massive Particle (WIMP) is one of the main candidates for the relic dark matter (DM).In the effective low-energy minimal supersymmetric standard model (effMSSM) the neutralino-nucleon spin and scalar cross sections in…
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…
The electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM) can account for a variety of experimental data. The lighest supersymmetric particle (LSP), which we take as the lightest neutralino, $\tilde \chi_1^0$, can…
In this thesis, we investigate various possibilities of Weakly Interacting Massive Particle (WIMP) dark matter (DM) and their implications. These possibilities are important because they challenge the viability of WIMP DM in light of tight…
We study the low scale predictions of supersymmetric standard model extended by $U(1)_{B-L}\times U(1)_{R}$ symmetry, obtained from $SO(10)$ breaking via a left-right supersymmetric model, imposing universal boundary conditions. Two singlet…
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 study constraints on the models of bosonic super-weakly interacting particle (super-WIMP) dark matter (DM) with DM masses $m_X \sim \mathcal{O}(1 - 100)$ keV from leptonic decays $M\rightarrow \ell \bar{\nu}_\ell + X$, where $M=B^\pm,…
We propose a Majoron-like extension of the Standard Model with an extra global $U(1)_X$-symmetry where neutrino masses are generated through an inverse seesaw mechanism at the 1-loop level. In contrast to the tree-level inverse seesaw, our…
The status of the constrained minimal supersymmetric standard model (CMSSM) will be discussed in light of our current understanding of the relic density after WMAP. A global likelihood analysis of the model is performed including data from…
We investigate Majorana dark matter in a new variant of $U(1)_{L_{\mu}-L_{\tau}}$ gauge extension of Standard Model, containing three additional neutral fermions $N_{e}, N_{\mu}, N_{\tau}$, along with a $(\bar{3},1,1/3)$ scalar Leptoquark…
We discuss phenomenological aspects of models whose scalar sector is extended by an isospin doublet scalar and a complex singlet scalar as an effective theory of supersymmetric models with mixed sneutrinos. In such models, the lighter of…
The Exceptional Supersymmetric Standard Model (E$_6$SSM) is a low energy alternative to the MSSM with an extra $U(1)$ gauge symmetry and three generations of matter filling complete 27-plet representations of $E_6$. This provides both new D…
$U(1)_X$SSM is the extension of the minimal supersymmetric standard model(MSSM) and its local gauge group is $SU(3)_C\times SU(2)_L \times U(1)_Y \times U(1)_X$. To obtain this model, three singlet new Higgs superfields and right-handed…
If all strongly interacting sparticles (the squarks and the gluinos) in an unconstrained minimal supersymmetric standard model (MSSM) are heavier than the corresponding mass lower limits in the minimal supergravity (mSUGRA) model, obtained…
The tightening of the constraints on the standard thermal WIMP scenario has forced physicists to propose alternative dark matter (DM) models. One of the most popular alternate explanations of the origin of DM is the non-thermal production…
Using a very minimal set of theoretical assumptions we derive a lower limit on the LSP mass in the MSSM. We only require that the LSP be the lightest neutralino, that it be responsible for the observed relic density and that the MSSM…
The minimal seesaw extension of the Standard Model requires two electroweak singlet fermions in order to accommodate the neutrino oscillation parameters at tree level. Here we consider a next to minimal extension where light neutrino masses…
We analyze the dark matter problem in the context of supersymmetric U(1)_{B-L} model. In this model, the lightest neutalino can be the B-L gaugino widetilde {Z}_{B-L} or the extra Higgsinos widetilde{chi}_{1,2} dominated. We compute the…