We report on charmonium measurements [J/ψ (1S), ψ ′ (2S), and χc (1P)] in p+p collisions at √ s = 200 GeV. We find that the fraction of J/ψ coming from the feed-down decay of ψ ′ and χc in the midrapidity region (|y| < 0.35) is 9.6 ± 2.4% and 32 ± 9%, respectively. We also present the pT and rapidity dependencies of the J/ψ yield measured via dielectron decay at midrapidity (|y| < 0.35) and via dimuon decay at forward rapidity (1.2 < |y| < 2.2). The statistical precision greatly exceeds that reported in our previous publication [Phys. Rev. Lett. 98, 232002 (2007)]. The new results are compared with other experiments and discussed in the context of current charmonium production models.

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The PHENIX collaboration has measured φ meson production in d+Au collisions at √ s N N = 200 GeV using the dimuon and dielectron decay channels. The φ meson is measured in the forward (backward) d-going (Au-going) direction, 1.2 < y < 2.2 (−2.2 < y < −1.2) in the transversemomentum (pT ) range from 1-7 GeV/c, and at midrapidity |y| < 0.35 in the pT range below 7 GeV/c. The φ meson invariant yields and nuclear-modification factors as a function of pT , rapidity, and centrality are reported. An enhancement of φ meson production is observed in the Au-going direction, while suppression is seen in the d-going direction, and no modification is observed at midrapidity relative to the yield in p+p collisions scaled by the number of binary collisions. Similar behavior was previously observed for inclusive charged hadrons and open heavy flavor indicating similar cold-nuclear-matter effects.

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We searched for the Φ −− (1860) pentaquark in the photoproduction process off the deuteron in the Ξ − π − decay channel using CLAS. The invariant mass spectrum of the Ξ − π − system does not indicate any statistically significant enhancement near the reported mass M = 1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90% confidence level upper limit of 0.7 nb for the photoproduction cross section of Φ −− (1860) with a consecutive decay into Ξ − π − in the photon energy range 4.5 GeV < Eγ < 5.5 GeV.