Multiplicity dependence of the average transverse momentum in pp, p-Pb, and Pb-Pb collisions at the LHC
Abstract
The average transverse momentum <pT> versus the charged-particle multiplicity Nch was measured in p-Pb collisions at a collision energy per nucleon-nucleon pair √{sNN}=5.02 TeV and in pp collisions at collision energies of √{s}=0.9,2.76, and 7 TeV in the kinematic range 0.15<pT<10.0 GeV/c and |η|<0.3 with the ALICE apparatus at the LHC. These data are compared to results in Pb-Pb collisions at √{sNN}=2.76 TeV at similar charged-particle multiplicities. In pp and p-Pb collisions, a strong increase of <pT> with Nch is observed, which is much stronger than that measured in Pb-Pb collisions. For pp collisions, this could be attributed, within a model of hadronizing strings, to multiple-parton interactions and to a final-state color reconnection mechanism. The data in p-Pb and Pb-Pb collisions cannot be described by an incoherent superposition of nucleon-nucleon collisions and pose a challenge to most of the event generators.
- Publication:
-
Physics Letters B
- Pub Date:
- December 2013
- DOI:
- 10.1016/j.physletb.2013.10.054
- arXiv:
- arXiv:1307.1094
- Bibcode:
- 2013PhLB..727..371A
- Keywords:
-
- Nuclear Experiment;
- High Energy Physics - Experiment
- E-Print:
- 18 pages, 4 captioned figures, 2 tables, authors from page 12, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/596