| Popis: |
Heavy resonances decaying into a pair of fundamental particles such as $jj$, $\ell^+\ell^-$, $\gamma\gamma$, and $\ell\nu$, are among the most common features to search for phenomena beyond the standard model (SM). Electroweak boson pair production, such as $WW$ or $ZZ$ with subsequent decays to $\ell\nu\ell'\nu'$ and $\ell\ell jj$ respectively, is a powerful test of the spontaneously broken gauge symmetry of the SM and can be also used to search for phenomena beyond the SM. There is a wide spectrum of theoretical models predicting these kinds of resonant signatures. This note covers several searches for these new phenomena conducted within ATLAS in 2011 and 2012 for the LHC 7 and 8 TeV center of mass energies respectively. No significant deviations from the SM have been observed and therefore, limits are set on the characteristic parameters of several new physics models. These benchmark models include new heavy $Z'/W'$ gauge bosons, chiral excitation of the SM weak gauge bosons, $Z^*/W^*$ Randal-Sundrum and ADD gravitons, Composite models for quarks, e.g. $q^*$ with substructure scale $\Lambda$, Quantum black holes, TeV$^{-1}$ Kaluza-Klein excitation of $\gamma/Z$ and more. |
