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Measurement of J / psi, psi-prime and upsilon total cross-sections in 800-GeV/c p - Si interactions

The E771 collaboration Alexopoulos, T ; Antoniazzi, L ; Arenton, M ; et al.

Phys.Lett.B 374 (1996) 271-276, 1996.

Inspire Record 400873 DOI 10.17182/hepdata.42316

We report on the analysis of Charmonium and Bottomium states produced in p-Si interactions at s =38.7 GeV . The data have been collected with the open geometry spectrometer of the E771 Experiment at the FNAL High Intensity Lab. J ψ , ψ′ and γ total cross sections as well as the ratio B(ψ′ → μμ)σ(ψ′) (B( J ψ → μμ)σ( J ψ )) have been measured. Results are compared with theoretical predictions and with results at other energies.

3 data tables

Table 1

The total inclusive cross section per nucleon has been evaluated assuming an atomic weight dependence of A**POWER with POWER = 0.920 +- 0.008.

Table 2

combined UPSI(1S) and UPSI(2S) cross section.

Table 3

No description provided.

Nuclear Dependence of Dimuon Production at 800-GeV

Alde, D.M. ; Baer, H.W. ; Carey, T.A. ; et al.

Phys.Rev.Lett. 64 (1990) 2479-2482, 1990.

Inspire Record 303588 DOI 10.17182/hepdata.19997

A precise measurement of the atomic-mass dependence of dimuon production induced by 800-GeV protons is reported. Over 450 000 muon pairs with dimuon mass M≥4 GeV were recorded from targets of H2, C, Ca, Fe, and W. The ratio of dimuon yield per nucleon for nuclei versus H2, R=YA/Y2H, is sensitive to modifications of the antiquark sea in nuclei. No nuclear dependence of this ratio is observed over the range of target-quark momentum fraction 0.1<xt<0.3. For xt<0.1 the ratio is slightly less than unity for the heavy nuclei. These results are compared with predictions of models of the European Muon Collaboration effect.

10 data tables

Table 1

High Mass trigger data.

Table 2

Intermediate Mass trigger data.

Table 3

Low Mass trigger data.