Electron identification and ZZ -->4l̳ (e̳, [mu]) cross section measurement with the CMS detector

We perform multiple analyses using generator-level information in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). In particular, we carry out three central investigations: the determination of electron efficiencies, electron fake rates, and ZZ -->4l(e, [mu]) cross sections. Reconstructed Z boson decays are used as a benchmark in association with our cut-based analysis. In the Z-->2e channel we find an overall electron efficiency of 77.0%± 1.3%, and electron fake rates are calculated to be (1.7 ± 0.5) . 10-3 and (0.6 ± 0.2) 10-3 for the photon jet and QCD channels, respectively. We calculate an expected total of 17 counts/fb-1 for ZZ-->4l, which we find to have a cross section of [sigma]zz-->4l = 180 ± 45 ± 6 fb (with statistical uncertainty listed before systematic uncertainty). From our analysis using generatorlevel information, we obtain a set of reconstruction-level techniques that will be useful once the LHC starts delivering pp collisions sometime in 2008.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2008

Author dc:creator

• Mooney, Michael Ryan

Advisor dc:contributor.advisor

• Christoph M. E. Paus.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/44759

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/44759