Measurement of charm and beauty production at central rapidity versus charged-particle multiplicity in proton-proton collisions at root s=7 TeV


Adam J., Adamova D., Aggarwal M. M., Rinella G. A., Agnello M., Agrawal N., ...Daha Fazla

JOURNAL OF HIGH ENERGY PHYSICS, cilt.2015, sa.9, 2015 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2015 Sayı: 9
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1007/jhep09(2015)148
  • Dergi Adı: JOURNAL OF HIGH ENERGY PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: Hadron-Hadron Scattering, SCATTERING
  • Bursa Uludağ Üniversitesi Adresli: Hayır

Özet

Prompt D meson and non-prompt J/psi yields are studied as a function of the multiplicity of charged particles produced in inelastic proton-proton collisions at a centre-of-mass energy of root s = 7 TeV. The results are reported as a ratio between yields in a given multiplicity interval normalised to the multiplicity-integrated ones (relative yields). They are shown as a function of the multiplicity of charged particles normalised to the average value for inelastic collisions (relative charged-particle multiplicity). D-0, D+ and D*+ mesons are measured in five p(T) intervals from 1 GeV/c to 20 GeV/c and for |y| < 0.5 via their hadronic decays. The D-meson relative yield is found to increase with increasing charged-particle multiplicity. For events with multiplicity six times higher than the average multiplicity of inelastic collisions, a yield enhancement of a factor about 15 relative to the multiplicity-integrated yield in inelastic collisions is observed. The yield enhancement is independent of transverse momentum within the uncertainties of the measurement. The D-0-meson relative yield is also measured as a function of the relative multiplicity at forward pseudo-rapidity. The non-prompt J/psi, i.e. the B hadron, contribution to the inclusive J/psi production is measured in the di-electron decay channel at central rapidity. It is evaluated for p(T) > 1.3 GeV/c and |y| < 0.9, and extrapolated to p(T) > 0. The fraction of non-prompt J/psi the inclusive J/psi yields shows no dependence on the charged-particle multiplicity at central rapidity. Charm and beauty hadron relative yields exhibit a similar increase with increasing charged-particle multiplicity. The measurements are compared to PYTHIA 8, EPOS 3 and percolation calculations.