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Measurements of inelastic J/psi and psi' photoproduction at HERA.

The ZEUS collaboration Chekanov, S. ; Krakauer, D. ; Magill, S. ; et al.

Eur.Phys.J.C 27 (2003) 173-188, 2003.

Inspire Record 601166 DOI 10.17182/hepdata.46546

The cross sections for inelastic photoproduction of J/psi and psi' mesons have been measured in ep collisions with the ZEUS detector at HERA, using an integrated luminosity of 38.0 pb-1. The events were required to have 0.1 < z < 0.9 and 50 < W < 180 GeV, where z is the fraction of the incident photon energy carried by the J/psi in the proton rest frame and W is the photon-proton centre-of-mass energy. The psi' to J/psi cross-section ratio was measured in the range 0.55 < z < 0.9. The J/psi data, for various ranges of transverse momentum, are compared to theoretical models incorporating colour-singlet and colour-octet matrix elements. Predictions of a next-to-leading-order colour-singlet model give a good description of the data, although there is a large normalisation uncertainty. The J/psi helicity distribution for z > 0.4 is compared to leading-order QCD predictions.

10 data tables

Table 1

Measurment of the total cross section, with various PT thresholds, in the high Z > 0.9 region.

Table 2

Ratio of cross section for PSI(2S) to J/PSI production. as a function of PT. Statistical errors only.

Table 3

Ratio of cross section for PSI(2S) to J/PSI production. as a function of W. Statistical errors only.

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EVIDENCE FOR THE F* MESON

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Badtke, D.H. ; et al.

Phys.Rev.Lett. 53 (1984) 2465, 1984.

Inspire Record 203890 DOI 10.17182/hepdata.20409

Evidence for a narrow state decaying into an F meson and a photon has been obtained in e+e− annihilation events at 29-GeV c.m. energy. This state lies 139.5 ± 8.3(stat.) ± 9.7(syst.) MeV above the F-meson mass and is consistent with the expected F* meson. The F mesons are identified by a peak in the K+K−Kπ± mass at 1.948±0.028±0.010 GeV.

2 data tables

Table 1

DATA REQUESTED FROM AUTHORS.

Table 2

IN (K+K-PI+) THE AUTHORS INCLUDE OTHER DECAY MODES SUCH AS (AK*0 K+),(PHI PI+),(K+ K- PI+,PI0),(K+ K- MU+ NU) WHICH CANNOT BE RESOLVED.