Speaker
Devin Harper
(University of Michigan)
Description
We have studied the sensitivity of the ATLAS detector for supersymmetric neutralino signals in the Zphoton + transverce missing energy (MET) and ZZ + MET final states in the Gauge Mediation Supersymmetry Breaking (GMSB) model in which the Higgsino-like neutralino is the next-to-lightest supersymmetric particle (NLSP). The neutralino could be pair produced either directly or indirectly and decay to Z or photon, plus a gravitino, the lightest supersymmetric particle (LSP), which would escape from the detector. This study considers the reaction of $\tilde{\chi}^{0}_{1} \tilde{\chi}^{0}_{1} \rightarrow Z\gamma \tilde{G}\tilde{G}$ and $\tilde{\chi}^{0}_{1} \tilde{\chi}^{0}_{1} \rightarrow ZZ \tilde{G}\tilde{G}$ decays to electron or muon pairs and used fully simulated ATLAS Monte Carlo events both for the signal and background. Based on the GMSB Higgsino-like neutralino model predictions, we expect that for an integrated luminosity of 2 fb$^{-1}$, ATLAS could detect the GMSB signal from the Higgsino-like neutralino that has a mass of 134 GeV in the Z photon + MET final state with a significance of 5.4$\sigma$ assuming 35% systematic uncertainty. For the ZZ + MET final state ATLAS could detect the GMSB signal for an integrated luminosity of 30 fb$^{-1}$, with a significance of 4.2$\sigma$ assuming 10% systematic uncertainty.
Author
Dr
Natalia Panikashvili
(University of Michigan)
