Production of $\pi^0$ and $\eta$ mesons in U$+$U collisions at $\sqrt{s_{_{NN}}}=192$ GeV

TL;DR

This study measures neutral meson production in uranium-uranium collisions at high energy, revealing suppression patterns similar to gold-gold collisions and providing insights into quark-gluon plasma effects.

Contribution

First measurement of $b0$ and $b7$ mesons in U+U collisions at 192 GeV, showing suppression patterns comparable to Au+Au collisions at 200 GeV.

Findings

Strong suppression of $b0$ and $b7$ at high transverse momentum in central U+U collisions.

$b7$/$b0$ ratios are constant across centralities and transverse momenta.

Suppression patterns are similar to those in Au+Au collisions at comparable participant nucleons.

Abstract

The PHENIX experiment at the Relativistic Heavy Ion Collider measured $\pi^0$ and $\eta$ mesons at midrapidity in U$+$U collisions at $\sqrt{s_{_{NN}}}=192$ GeV in a wide transverse momentum range. Measurements were performed in the $\pi^0(\eta)\rightarrow\gamma\gamma$ decay modes. A strong suppression of $\pi^0$ and $\eta$ meson production at high transverse momentum was observed in central U$+$U collisions relative to binary scaled $p$$+$$p$ results. Yields of $\pi^0$ and $\eta$ mesons measured in U$+$U collisions show similar suppression pattern to the ones measured in Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV for similar numbers of participant nucleons. The $\eta$/$\pi^0$ ratios do not show dependence on centrality or transverse momentum, and are consistent with previously measured values in hadron-hadron, hadron-nucleus, nucleus-nucleus, and $e^+e^-$ collisions.