Measurement of the production cross sections for a Z boson and one or more b jets in pp collisions at root s=7 TeV


Chatrchyan S., Khachatryan V., Sirunyan A. M., Tumasyan A., Adam W., Bergauer T., ...Daha Fazla

JOURNAL OF HIGH ENERGY PHYSICS, sa.6, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: Sayı: 6
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1007/jhep06(2014)120
  • Dergi Adı: JOURNAL OF HIGH ENERGY PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: Jet physics, Hadron-Hadron Scattering
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The production of a Z boson, decaying into two leptons and produced in association with one or more b jets, is studied using proton-proton collisions delivered by the LHC at a centre-of-mass energy of 7 TeV. The data were recorded in 2011 with the CMS detector and correspond to an integrated luminosity of 5 fb(-1). The Z(ll) + b-jets cross sections (where ll = mu mu or ee) are measured separately for a Z boson produced with exactly one b jet and with at least two b jets. In addition, a cross section ratio is extracted for a Z boson produced with at least one b jet, relative to a Z boson produced with at least one jet. The measured cross sections are compared to various theoretical predictions, and the data favour the predictions in the five-flavour scheme, where b quarks are assumed massless. The kinematic properties of the reconstructed particles are compared with the predictions from the MadGraph event generator using the pythia parton shower simulation.