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arXiv · 1802.09011

$η'$ Production in Nucleus-Nucleus collisions as a probe of chiral dynamics

Giorgio Torrieri
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Abstract

We argue that, because of the peculiar properties of the $η'$ meson, it is a promising probe of "chiral" dynamics. In particular, we show that a rotating gluon-dominated plasma might lead to an enhanced production of $η'$ w.r.t. statistical model expectations. The presence of a strong topological susceptibility might give a similar effect. In both cases, unlike the statistical model,we expect a non-trivial dependence on event geometry, such as initial volume and impact parameter. Hence, an observation of $η'/π^0$ ratio depending strongly on impact parameter might be a good indication of chiral effects, either from vorticity or topological phases of QCD

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Giorgio Torrieri. 2018-06-19. $η'$ Production in Nucleus-Nucleus collisions as a probe of chiral dynamics. https://doi.org/10.1103/physrevc.98.014901

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