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arXiv · 2006.07707

Measurement of the azimuthal anisotropy of $Υ$(1S) and $Υ$(2S) mesons in PbPb collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV

CMS Collaboration
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Abstract

The second-order Fourier coefficients ($v_2$) characterizing the azimuthal distribution of $Υ$(1S) and $Υ$(2S) mesons arising from PbPb collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV are studied. The $Υ$ mesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The data set corresponds to an integrated luminosity of 1.7 nb$^{-1}$. The scalar product method is used to extract the $v_2$ coefficients of the azimuthal distribution. Results are reported for the rapidity range $|y|$ $\lt$ 2.4, with the transverse momentum 0 $\lt$ $p_\mathrm{T}$ $\lt$ 50 GeV/$c$, and in three centrality ranges of 10-30%, 30-50% and 50-90%. In contrast to the J/$ψ$ mesons, the measured $v_2$ values for the $Υ$ mesons are found to be consistent with zero.

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CMS Collaboration. 2021-06-06. Measurement of the azimuthal anisotropy of $Υ$(1S) and $Υ$(2S) mesons in PbPb collisions at $\sqrt{s_\mathrm{NN}} =$ 5.02 TeV. https://doi.org/10.1016/j.physletb.2021.136385

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