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arXiv · 2205.15087

An analysis of the spin density matrix of quarkonium in heavy ion collisions

Kayman J. Gonçalves·Giorgio Torrieri
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Abstract

In this addendum to [1], we apply the techniques developed in that paper to the $J/Ψ$ and $Υ$ spin alignement measurements in [2]. We argue that while the data points to a maximally impure density matrix, consistent with Cooper-Frye/Statistical model freeze-out, a measurement of the dependence of the $ϕ$-sensitive coefficients on the azimuthal angle with respect to the reaction plane would be the crucial test of this conclusion.

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Kayman J. Gonçalves, Giorgio Torrieri. 2022-05-19. An analysis of the spin density matrix of quarkonium in heavy ion collisions. https://arxiv.org/abs/2205.15087

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