Searches for gluino mediated sbottom production with the ATLAS detector

Sellers, Graham Searches for gluino mediated sbottom production with the ATLAS detector. Doctor of Philosophy thesis, University of Liverpool.

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Abstract

A search for the supersymmetric process of gluino mediated sbottom produc- tion is presented. This search was carried out using 2.05 fb−1 of 7 TeV proton- proton collisions in the ATLAS detector at the LHC. The data used were collected during the 2011 ATLAS run. In the search, six distinct signal regions are defined in order to identify can- didate events for the signal process. These regions are distinguished by requiring events to possess an effective mass of at least 500 GeV, 700 GeV or 900 GeV and by requiring at least 1 b-jet or at least 2 b-jets in the final state. The data ob- served in these signal regions are compared to Monte Carlo simulation of known Standard Model processes, which form the background to this search. No excess in the data above the Standard Model background is seen in any of the signal regions and therefore limits are set on the exclusion of this supersym- metric process in the gluino-sbottom mass plane. The limits set are derived from two distinctly different statistical foundations, one using a frequentist approach and the other using a Bayesian approach. The two methods are compared in the final limits they provide and are found to be in good agreement with one another.

Item Type:	Thesis (Doctor of Philosophy)
Additional Information:	Date: 2012-11 (completed)
Subjects:	?? QC ??
Divisions:	Faculty of Science and Engineering > School of Physical Sciences
Depositing User:	Symplectic Admin
Date Deposited:	21 Jan 2013 10:27
Last Modified:	16 Dec 2022 04:37
DOI:	10.17638/00008333
Supervisors:	Burdin, Sergey
URI:	https://livrepository.liverpool.ac.uk/id/eprint/8333