Enhanced production of multi-strange hadrons in high-multiplicity proton-proton collisions

0488769 - ÚJF 2018 RIV GB eng J - Journal Article
Adam, J. - Adamová, Dagmar - Bielčík, J. - Bielčíková, Jana - Broz, M. - Čepila, J. - Contreras, J. G. - Eyyubova, G. - Ferencei, Jozef - Horák, D. - Křížek, Filip - Kučera, Vít - Mareš, Jiří A. - Petráček, V. - Pospíšil, Jan - Šumbera, Michal - Vaňát, Tomáš - Závada, Petr … Total 1003 authors
Enhanced production of multi-strange hadrons in high-multiplicity proton-proton collisions.
Nature Physics. Roč. 13, č. 6 (2017), s. 535-539. ISSN 1745-2473. E-ISSN 1745-2481
R&D Projects: GA MŠMT(CZ) LG15052
Institutional support: RVO:68378271 ; RVO:61389005
Keywords : ALICE collaboration * heavy ion collisions * multiplicity
OECD category: Nuclear physics; Particles and field physics (FZU-D)
Impact factor: 22.727, year: 2017

At sufficiently high temperature and energy density, nuclear matter undergoes a transition to a phase in which quarks and gluons are not confined: the quark-gluon plasma (QGP)(1). Such an exotic state of strongly interacting quantum chromodynamics matter is produced in the laboratory in heavy nuclei high-energy collisions, where an enhanced production of strange hadrons is observed(2-6). Strangeness enhancement, originally proposed as a signature of QGP formation in nuclear collisions(7), is more pronounced for multi-strange baryons. Several effects typical of heavy-ion phenomenology have been observed in high-multiplicity proton-proton (pp) collisions(8,9), but the enhanced production of multi-strange particles has not been reported so far. Here we present the first observation of strangeness enhancement in high-multiplicity proton-proton collisions. We find that the integrated yields of strange and multi-strange particles, relative to pions, increases significantly with the event charged-particle multiplicity. The measurements are in remarkable agreement with the p-Pb collision results(10,11), indicating that the phenomenon is related to the final system created in the collision. In high-multiplicity events strangeness production reaches values similar to those observed in Pb-Pb collisions, where a QGP is formed.
Permanent Link: http://hdl.handle.net/11104/0283307