Measurements of fiducial cross-sections for t(t)over-bar production with one or two additional b-jets in pp collisions at root s=8 TeV using the ATLAS detector


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Aad G., Abbott B., Abdallah J., Abdinov O., Aben R., Abolins M., ...Daha Fazla

EUROPEAN PHYSICAL JOURNAL C, cilt.76, sa.1, 2016 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 76 Sayı: 1
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1140/epjc/s10052-015-3852-4
  • Dergi Adı: EUROPEAN PHYSICAL JOURNAL C
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Gazi Üniversitesi Adresli: Hayır

Özet

Fiducial cross-sections for t (t) over bar 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 t (t) over bar 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 e mu 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 (e mu, mu mu, 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 t (t) over bar production with two additional b-jets to t (t) over bar production with any two additional jets. All measurements are in good agreement with recent theory predictions.