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arXiv · hep-ph/0112017

Resonance Production at STAR

Eugene T. Yamamoto
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Abstract

We present the first measurement of mid-rapidity $ϕ$ vector meson production in $Au+Au$ collisions at RHIC ($\sqrt{s_{_{NN}}} =130$ GeV) from the STAR detector. For the 11% most central collisions, the slope parameter from an exponential fit to the transverse mass distribution is $T=$~379$\pm$51(stat) $\pm$ 45(syst)~MeV, the yield $dN/dy$ $=5.73\pm$0.37(stat)$\pm$ 0.57(syst) per event and the ratio $N_ϕ/N_{h^-}$ is found to be 0.021$\pm$0.001(stat)$\pm$ 0.03(syst). We currently place the value of the $N_ϕ/N_{K^-}$ ratio between 0.10 and 0.16. The measured ratios $N_ϕ/N_{h^-}$ and $N_ϕ/N_{K^-}$, as well as $T$ for the $ϕ$ meson at mid-rapidity do not change for the selected centrality bins.

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Eugene T. Yamamoto. 2001-12-03. Resonance Production at STAR. https://doi.org/10.1142/9789812778048_0025

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