= 200 Gev

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چکیده

We present the results on the mid-rapidity φ meson production in the K + K − decay channel in Au + Au collisions at √ s N N = 200 GeV measured by the PHENIX experiment at RHIC. The spectral shape of the φ resonance, studied at different collision centralities, is consistent with the particle data book. The transverse mass spectra are measured in four centrality bins. The inverse slopes (T), yields (dN/dy) and particle ratios are studied as a function of centrality. The nuclear modification factor is measured through the ratio, R CP , of central to peripheral yields normalized to the number of nucleon-nucleon collisions. The R CP of the φ mesons is less than unity and is comparable to that of pions rather than R CP ∼ 1 observed for protons and anti-protons.

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تاریخ انتشار 2004