The first measurement of the Υð1SÞ elliptic flow coefficient (v2) is performed at forward rapidity (2.5 < y < 4) in Pb–Pb collisions at ffiffiffiffiffiffiffiffi sNN p ¼ 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 (p T ) up to 15 GeV=c in the 5%–60% centrality interval. The measured Υð1SÞv2 is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v2 coefficient in 2 < p T < 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 Υð1SÞ 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.
{Measurement of $\Upsilon(1{\rm S})$ elliptic flow at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=5.02$ TeV} / The ALICE collaboration, ., Acharya, S., Adamová, D., Adhya, S.P., Adler, A., Adolfsson, J., Aggarwal, M.M., Aglieri Rinella, G., Agnello, M., Agrawal, N., Ahammed, Z., Ahmad, S., Ahn, S.U., Aiola, S., Akindinov, A., Al-Turany, M., Alam, S.N., Albuquerque, D.S.D., Aleksandrov, D., Alessandro, B., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 1092-0145. - 123:19(2019). [10.1103/PhysRevLett.123.192301]
{Measurement of $\Upsilon(1{\rm S})$ elliptic flow at forward rapidity in Pb-Pb collisions at $\sqrt{s_{\rm{NN}}}=5.02$ TeV}
L. CunqueiroMembro del Collaboration Group
;
2019
Abstract
The first measurement of the Υð1SÞ elliptic flow coefficient (v2) is performed at forward rapidity (2.5 < y < 4) in Pb–Pb collisions at ffiffiffiffiffiffiffiffi sNN p ¼ 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 (p T ) up to 15 GeV=c in the 5%–60% centrality interval. The measured Υð1SÞv2 is consistent with 0 and with the small positive values predicted by transport models within uncertainties. The v2 coefficient in 2 < p T < 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 Υð1SÞ 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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
