Journal of High Energy Physics > 2015 > 2015 > 11 > 1-48
Measurement of the t t ¯ W $$ t\overline{t}W $$ and t t ¯ Z $$ t\overline{t}Z $$ production cross sections in pp collisions at s = 8 $$ \sqrt{s}=8 $$ TeV with the ATLAS detector
Source
Abstract
The production cross sections of top-quark pairs in association with massive vector bosons have been measured using data from pp collisions at s = 8 $$ \sqrt{s}=8 $$ TeV. The dataset corresponds to an integrated luminosity of 20.3 fb−1 collected by the ATLAS detector in 2012 at the LHC. Final states with two, three or four leptons are considered. A fit to the data considering the t t ¯ W $$ t\overline{t}W $$ and t t ¯ Z $$ t\overline{t}Z $$ processes simultaneously yields a significance of 5.0σ (4.2σ) over the background-only hypothesis for t t ¯ W $$ t\overline{t}W $$ ( t t ¯ Z $$ t\overline{t}Z $$ ) production. The measured cross sections are σ t t ¯ W = 369 − 91 + 100 $$ {\sigma}_{t\overline{t}W}={369}_{-91}^{+100} $$ fb and σ t t ¯ Z = 176 − 52 + 58 $$ {\sigma}_{t\overline{t}Z}={176}_{-52}^{+58} $$ fb. The background-only hypothesis with neither t t ¯ W $$ t\overline{t}W $$ nor t t ¯ Z $$ t\overline{t}Z $$ production is excluded at 7.1σ. All measurements are consistent with next-to-leading-order calculations for the t t ¯ W $$ t\overline{t}W $$ and t t ¯ Z $$ t\overline{t}Z $$ processes.
Identifiers
journal e-ISSN : | 1029-8479 |
DOI | 10.1007/JHEP11(2015)172 |
Authors
B. Abbott
- University of Oklahoma, Homer L. Dodge Department of Physics and Astronomy, Norman, United States of America