Charged particle multiplicities in pp interactions at sqrt(s) = 0.9, 2.36, and 7 TeV
- Yerevan Physics Institute (Aremenia)
Measurements of primary charged hadron multiplicity distributions are presented for non-single-diffractive events in proton-proton collisions at centre-of-mass energies of sqrt(s) = 0.9, 2.36, and 7 TeV, in five pseudorapidity ranges from |eta|<0.5 to |eta|<2.4. The data were collected with the minimum-bias trigger of the CMS experiment during the LHC commissioning runs in 2009 and the 7 TeV run in 2010. The multiplicity distribution at sqrt(s) = 0.9 TeV is in agreement with previous measurements. At higher energies the increase of the mean multiplicity with sqrt(s) is underestimated by most event generators. The average transverse momentum as a function of the multiplicity is also presented. The measurement of higher-order moments of the multiplicity distribution confirms the violation of Koba-Nielsen-Olesen scaling that has been observed at lower energies.
- 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 Colloboration
- OSTI ID:
- 1176781
- Report Number(s):
- FERMILAB-PUB-10-626-CMS; CERN-PH-EP-2010-048; CMS-QCD-10-004; ArticleNumber: 79; arXiv eprint number arXiv:1011.5531
- Journal Information:
- Journal of High Energy Physics (Online), Vol. 2011, Issue 1; ISSN 1029-8479
- Publisher:
- Springer Berlin
- Country of Publication:
- United States
- Language:
- English
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