Multiplicity dependence of light-flavor hadron production in pp collisions at root s=7 TeV

0503125 - ÚJF 2020 RIV US eng J - Journal Article
Acharya, S. - Acosta, F. T. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Contreras, J. G. - Horák, D. - Křížek, Filip - Kučera, Vít - Kushpil, Svetlana - Lavička, R. - Mareš, Jiří A. - Petráček, V. - Šumbera, Michal - Závada, Petr … Total 1021 authors
Multiplicity dependence of light-flavor hadron production in pp collisions at root s=7 TeV.
Physical Review C. Roč. 99, č. 2 (2019), č. článku 024906. ISSN 2469-9985. E-ISSN 2469-9993
R&D Projects: GA MŠMT LTT18002
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * heavy ion collisions * LHC
OECD category: Nuclear physics; Particles and field physics (FZU-D)
Impact factor: 2.988, year: 2019
Method of publishing: Open access
https://doi.org/10.1103/PhysRevC.99.024906

Comprehensive results on the production of unidentified charged particles, pi(+/-), K-+/-, K-s(0), K*(892)(0), p, (p) over bar, phi(1020), Lambda, (Lambda) over bar, Xi(-) , (Xi) over bar (+), Omega(-), and (Omega) over bar (+) hadrons in proton-proton (pp) collisions at root s = 7 TeV at midrapidity (vertical bar y vertical bar < 0.5) as a function of charged-particle multiplicity density are presented. In order to avoid autocorrelation biases, the actual transverse momentum (p(T)) spectra of the particles under study and the event activity are measured in different rapidity windows. In the highest multiplicity class, the charged-particle density reaches about 3.5 times the value measured in inelastic collisions. While the yield of protons normalized to pions remains approximately constant as a function of multiplicity, the corresponding ratios of strange hadrons to pions show a significant enhancement that increases with increasing strangeness content. Furthermore, all identified particleto-pion ratios are shown to depend solely on charged-particle multiplicity density, regardless of system type and collision energy. The evolution of the spectral shapes with multiplicity and hadron mass shows patterns that are similar to those observed in p-Pb and Pb-Pb collisions at Large Hadron Collider energies. The obtained p(T), distributions and yields are compared to expectations from QCD-based pp event generators as well as to predictions from thermal and hydrodynamic models. These comparisons indicate that traces of a collective, equilibrated system are already present in high-multiplicity pp collisions.
Permanent Link: http://hdl.handle.net/11104/0294946