Measurement of neutral strange particle production in the underlying event in proton-proton collisions at sqrt(s) = 7 TeV
Measurements are presented of the production of primary K(S)0 and Lambda particles in proton-proton collisions at sqrt(s) = 7 TeV in the region transverse to the leading charged-particle jet in each event. The average multiplicity and average scalar transverse momentum sum of K(S)0 and Lambda particles measured at pseudorapidities abs(eta) < 2 rise with increasing charged-particle jet pt in the range 1-10 GeV and saturate in the region 10-50 GeV. The rise and saturation of the strange particle yields and transverse momentum sums in the underlying event are similar to those observed for inclusive charged particles, which confirms the impact-parameter picture of multiple parton interactions. The results are compared to recent tunes of the PYTHIA Monte Carlo event generator. The PYTHIA simulations underestimate the data by 15-30% for K(S)0 mesons and by about 50% for Lambda baryons, a deficit similar to that observed for the inclusive strange particle production in non-single-diffractive proton-proton collisions. The constant strange- to charged-particle activity ratios and the similar trends for mesons and baryons indicate that the multiparton-interaction dynamics is decoupled from parton hadronization, which occurs at a later stage.
- Research Organization:
- Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), High Energy Physics (HEP)
- Contributing Organization:
- CMS Collaboration
- DOE Contract Number:
- AC02-07CH11359
- OSTI ID:
- 1155838
- Report Number(s):
- CERN-PH-EP-2013-086; CMS-QCD-11-010; arXiv eprint number arXiv:1305.6016
- Journal Information:
- Physical Review. D, Particles, Fields, Gravitation and Cosmology, Vol. 88, Issue 5; ISSN 1550-7998
- Publisher:
- American Physical Society (APS)
- Country of Publication:
- United States
- Language:
- English
Similar Records
Production of $ {\textrm{K}}_{\textrm{S}}^0 $, Λ ($ \overline{\Lambda}$), Ξ±, and Ω± in jets and in the underlying event in pp and p–Pb collisions
Measurement of the production of charm jets tagged with D0 mesons in pp collisions at $\sqrt{\mathrm{s}}=7$ TeV