Searches for New Physics in the Standard Model's Electroweak Sector: Quartic Anomalous Couplings with Vector Boson Fusion and Flavor Changed Neutral Current in the $SU(3{)}_C\otimes SU(3{)}_L\otimes U(1{)}_X$ model

Abstract

In this thesis we investigated, at partonic level and leading order, the LHC potencial operating with $\sqrt{s}=14$ TeV and integrated luminosity of $L=100{fb}^{-1}$ to probe "pure" (without triple vertex contributions) anomalous electroweak quartic couplings, $WWWW$ and $WWZZ$, in the semileptonic $pp\to l^{\pm }{\nu }_{l}jjjj$ channel, enhanced by the Vector Boson Fusion collider signatures. Deviations on SM quartic couplings were parameterized in a model independent approach, realized linearly ($L_{S0}$ and $L_{S1}$ operators) or not ($L_4$ and $L_5$ operators), on the basis of effective lagrangians. Being our analysis essentially events counting-and-cut based, we took into account all possible backgrounds (irreducible, QCD and top quarks processes) considered at $\mathcal{O}({\alpha }_{em}^6)$, ${\cal O(α_{em}^{4}α_{s}^{2})$ and $\mathcal{O}({\alpha }_{em}^2{\alpha }_s^4)$. In this way, we have obtained the following constraints for the non-linear ${\alpha }_4$ and ${\alpha }_5$ anomalous couplings: $|{\alpha }_{4,5}|\lesssim 0.01$ to 0.02 at 3$\sigma$. Based on non-linear results, we have estimated, for a specific choice of factorization and renormalization scale, the linear parameters $f_0$ and $f_1$ constraints as $-22\le \frac{f_0}{{\Lambda }^4}({TeV}^{-4})\le 20,and-26\le \frac{f_1}{{\Lambda }^4}({TeV}^{-4})\le 24$ at 3$\sigma$. On a different approach, manipulating one extension of the SM named $331_{RHN}$, we have evaluated the contribution of new sources of FCNC for the difference of mass of neutral meson systems, $K_0-\overline{K_0}$, $D^0-\overline{D^0}$ and $B_d^0-\overline{B_d^0}$. Bounds related to these systems may be significantly strengthened in the presence of these new interactions allowing stronger constraints on the parameter space of the model.

PhD Thesis (UFABC, 2012). 146 pages with many figures. In Portuguese

References in corpus (4)

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• PHANTOM: a Monte Carlo event generator for six parton final states at high energy colliders
• TeV Scale Left Right Symmetry and Flavor Changing Neutral Higgs Effects
• Possible experimental signatures at the LHC of strongly interacting electro-weak symmetry breaking