Measurement of the cross section ratio σttbarbbbar /σttbarjj in pp collisions at √{ s} = 8 TeV
Abstract
The first measurement of the cross section ratio σttbarbbbar /σttbarjj is presented using a data sample corresponding to an integrated luminosity of 19.6 fb-1 collected in pp collisions at √{ s} = 8 TeV with the CMS detector at the LHC. Events with two leptons (e or μ) and four reconstructed jets, including two identified as b quark jets, in the final state are selected. The ratio is determined for a minimum jet transverse momentum pT of both 20 and 40 GeV/c. The measured ratio is 0.022 ± 0.003 (stat) ± 0.005 (syst) for pT > 20 GeV / c. The absolute cross sections σttbarbbbar and σttbarjj are also measured. The measured ratio for pT > 40 GeV / c is compatible with a theoretical quantum chromodynamics calculation at next-to-leading order.
- Publication:
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Physics Letters B
- Pub Date:
- June 2015
- DOI:
- 10.1016/j.physletb.2015.04.060
- Bibcode:
- 2015PhLB..746..132K
- Keywords:
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- CMS;
- Physics;
- Top physics