DOI

  • ALICE Collaboration

The first measurement of the γ(1S) elliptic flow coefficient (v2) is performed at forward rapidity (2.5<y<4) in Pb-Pb collisions at sNN=5.02 TeV with the ALICE detector at the LHC. The results are obtained with the scalar product method and are reported as a function of transverse momentum (pT) up to 15 GeV/c in the 5%-60% centrality interval. The measured γ(1S)v2 is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v2 coefficient in 2<pT<15 GeV/c is lower than that of inclusive J/ψ mesons in the same pT interval by 2.6 standard deviations. These results, combined with earlier suppression measurements, are in agreement with a scenario in which the γ(1S) production in Pb-Pb collisions at LHC energies is dominated by dissociation limited to the early stage of the collision, whereas in the J/ψ case there is substantial experimental evidence of an additional regeneration component.

Язык оригиналаанглийский
Номер статьи192301
Число страниц13
ЖурналPhysical Review Letters
Том123
Номер выпуска19
DOI
СостояниеОпубликовано - 6 ноя 2019

    Предметные области Scopus

  • Физика и астрономия (все)

ID: 49015367