$\ensuremath{\phi}$ meson production in the forward/backward rapidity region in Cu + Au collisions at $\sqrt{{s}_{\mathit{NN}}}=200$ GeV

$ϕ$ meson production in the forward/backward rapidity region in Cu + Au collisions at $\sqrt{s_{NN}} = 200$ GeV

A. Adare et al. (PHENIX Collaboration)

Phys. Rev. C 93, 024904 – Published 4 February 2016

Abstract

The PHENIX experiment at the Relativistic Heavy Ion Collider has measured $ϕ$ meson production and its nuclear modification in asymmetric $Cu + Au$ heavy-ion collisions at $\sqrt{s_{NN}} = 200$ GeV at both forward Cu-going direction $(1.2 < y < 2.2)$ and backward Au-going direction $(- 2.2 < y < - 1.2)$ rapidities. The measurements are performed via the dimuon decay channel and reported as a function of the number of participating nucleons, rapidity, and transverse momentum. In the most central events, 0%–20% centrality, the $ϕ$ meson yield integrated over $1 < p_{T} < 5$ GeV/ $c$ prefers a smaller value, which means a larger nuclear modification, in the Cu-going direction compared to the Au-going direction. Additionally, the nuclear-modification factor in $Cu + Au$ collisions averaged over all centrality is measured to be similar to the previous PHENIX result in $d + Au$ collisions for these rapidities.