In:
Journal of High Energy Physics, Springer Science and Business Media LLC, Vol. 2019, No. 2 ( 2019-02)
Abstract:
The second ( v 2 ) and third ( v 3 ) flow harmonic coefficients of J/ ψ mesons are measured at forward rapidity (2.5 〈 y 〈 4.0) in Pb-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}}=5.02 $$ s N N = 5.02 TeV with the ALICE detector at the LHC. Results are obtained with the scalar product method and reported as a function of transverse momentum, p T , for various collision centralities. A positive value of J/ ψ v 3 is observed with 3.7 σ significance. The measurements, compared to those of prompt D 0 mesons and charged particles at mid-rapidity, indicate an ordering with v n (J/ ψ ) 〈 v n (D 0 ) 〈 v n (h ± ) (n = 2, 3) at low and intermediate p T up to 6 GeV/ c and a convergence with v 2 (J/ ψ ) ≈ v 2 (D 0 ) ≈ v 2 (h ± ) at high p T above 6–8 GeV/ c . In semi-central collisions (5–40% and 10–50% centrality intervals) at intermediate p T between 2 and 6 GeV/ c , the ratio v 3 / v 2 of J/ ψ mesons is found to be significantly lower (4.6 σ ) with respect to that of charged particles. In addition, the comparison to the prompt D 0 -meson ratio in the same p T interval suggests an ordering similar to that of the v 2 and v 3 coefficients. The J/ ψ v 2 coefficient is further studied using the Event Shape Engineering technique. The obtained results are found to be compatible with the expected variations of the eccentricity of the initial-state geometry.
Type of Medium:
Online Resource
ISSN:
1029-8479
DOI:
10.1007/JHEP02(2019)012
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
2019
detail.hit.zdb_id:
2027350-2
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