Nötrino-elektron elastik saçılım kanalından düşük enerjilerde little Higgs model araştırmaları

The standard model (SM) of particle physics had aptly achieved a remarkable success in describing the interactions of the subatomic world. Some serious problems, however, put the SM in a critical situation, doubted its ability to be the whole story of nature and motivated physicists to look for physics beyond the SM (BSM). The hierarchy problem, which is one of the focal points in this thesis work, is a major problem within the SM by which the Higgs mass is unwillingly large. In this work, the origin of the Higgs by the famous Higgs mechanism is first examined and then, as a solution to the hierarchy problem, a model-dependent BSM theory dubbed little Higgs models (LHMs) is extensively studied. In the scope of LHMs, two different classes known as SU(5) littlest Higgs model (LTHM) with no T-parity and SU(3) simple little Higgs model (SLHM) are theoretically and analytically examined using (anti)neutrino-electron scattering channel at low energies. Theoretically, taking into consideration the flavor conserving (FC) and flavor violating (FV) processes, the corrections of both of these models to the SM (anti)neutrino electron scattering cross section are calculated. Experimentally, then, 90% C.L. (two sigma equivalence) bounds on the relevant free parameters of both models are obtained utilizing TEXONO (antineutrino-electron scattering) and LSND (neutrino-electron scattering) experiments.