Measurements of fiducial cross-sections for (Formula presented.) production with one or two additional b-jets in pp collisions at √s = 8 TeV using the ATLAS detector
Number of Authors: 2858
2016 (English)In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 76, no 1, 1-37 p., 11Article in journal (Refereed) PublishedText
Fiducial cross-sections for tt¯ production with one or two additional b-jets are reported, using an integrated luminosity of 20.3 fb-1 of proton–proton collisions at a centre-of-mass energy of 8 TeV at the Large Hadron Collider, collected with the ATLAS detector. The cross-section times branching ratio for tt¯ events with at least one additional b-jet is measured to be 950 ± 70 (stat.) -190 +240 (syst.) fb in the lepton-plus-jets channel and 50 ± 10 (stat.) -10 +15 (syst.) fb in the eμ channel. The cross-section times branching ratio for events with at least two additional b-jets is measured to be 19.3 ± 3.5 (stat.) ± 5.7 (syst.) fb in the dilepton channel (eμ, μμ, and ee) using a method based on tight selection criteria, and 13.5 ± 3.3 (stat.) ± 3.6 (syst.) fb using a looser selection that allows the background normalisation to be extracted from data. The latter method also measures a value of 1.30 ± 0.33 (stat.) ± 0.28 (syst.)% for the ratio of tt¯ production with two additional b-jets to tt¯ production with any two additional jets. All measurements are in good agreement with recent theory predictions.
Place, publisher, year, edition, pages
Springer-Verlag New York, 2016. Vol. 76, no 1, 1-37 p., 11
IdentifiersURN: urn:nbn:se:kth:diva-181801DOI: 10.1140/epjc/s10052-015-3852-4ISI: 000370645300001ScopusID: 2-s2.0-84953854901OAI: oai:DiVA.org:kth-181801DiVA: diva2:900575
QC 201602042016-02-042016-02-042016-03-23Bibliographically approved