Production of $\psi$ (3100) and $\psi^{\prime}$ (3700) in p-Be Collisions at 400-GeV

Snyder, H.D. ; Hom, D.C. ; Lederman, L.M. ; et al.
Phys.Rev.Lett. 36 (1976) 1415, 1976.
Inspire Record 108462 DOI 10.17182/hepdata.21117

We report preliminary results on the production of electron-positron pairs in the mass range 2.5 to 4 GeV in 400-GeV p-Be interactions. Production cross sections of the ψ(3100) near x=0 as a function of pt, x, and the decay angle are presented and implications of these new data for single direct leptons are discussed. A ψ′(3700) signal is observed at a level corresponding to σ(ψ′)σ(ψ)=(10±3)%.

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Study of the high mass dimuon continuum in 400-GeV proton - nucleus collisions

Kaplan, D.M. ; Fisk, R.J. ; Ito, A.S. ; et al.
Phys.Rev.Lett. 40 (1978) 435, 1978.
Inspire Record 122485 DOI 10.17182/hepdata.20947

The mass spectrum of muon pairs in the range 5 to 15 GeV is studied in the inclusive reaction p+nucleus→μ++μ−+anything. The ϒ and continuum distribution are presented as is the A dependence of the continuum. Comparison with a parton-annihilation model yields a sea-quark distribution.

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Evidence for the Upsilon'' and a Search for New Narrow Resonances

Ueno, K. ; Brown, B.C. ; Brown, C.N. ; et al.
Phys.Rev.Lett. 42 (1979) 486-489, 1979.
Inspire Record 132766 DOI 10.17182/hepdata.42707

The production of the ϒ family in proton-nucleus collisions is clarified by a sixfold increase in statistics. Constraining ϒ,ϒ′ masses to those observed at DORIS we find the statistical significance of the ϒ′′ to be 11 standard deviations. The dependence of ϒ production on pt, y, and s is presented. Limits for other resonance production in the mass range 4-18 GeV are determined.

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Observation of a dimuon resonance at 9.5-GeV in 400-GeV proton - nucleus collisions

The E288 collaboration Herb, S.W. ; Hom, D.C. ; Lederman, L.M. ; et al.
Phys.Rev.Lett. 39 (1977) 252-255, 1977.
Inspire Record 120368 DOI 10.17182/hepdata.42613

Dimuon production is studied in 400-GeV proton-nucleus collisions. A strong enhancement is observed at 9.5 GeV mass in a sample of 9000 dimuon events with a mass $m_{\mu^+\mu^-} \to$ 5 GeV.

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Study of scaling in hadronic production of dimuons

Yoh, J.K. ; Herb, S.W. ; Hom, D.C. ; et al.
Phys.Rev.Lett. 41 (1978) 684, 1978.
Inspire Record 130804 DOI 10.17182/hepdata.3337

We present proton-nucleus dimuon-production cross sections for masses between 4 and 15 GeV, center-of-mass rapidities between -0.23 and 0.6 and incident energies of 200, 300, and 400 GeV. The data confirm scaling to the 20% level. The dependence of continuum 〈pT〉 on beam energy is also presented.

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Dimuon Production in 800 GeV Proton Nucleus Collisions

Brown, C.N. ; Cooper, W.E. ; Finley, D. ; et al.
Phys.Rev.Lett. 63 (1989) 2637-2640, 1989.
Inspire Record 288346 DOI 10.17182/hepdata.20031

A measurement of continuum dimuon production in proton-copper collisions at 800-GeV incident energy is presented. The dimuons observed in this experiment cover the mass range from 6.5 to 18 GeV near y=0 in the proton-nucleon center-of-momentum frame. Scaling forms of the cross section for the continuum are compared with the results of other experiments in the context of the parton model and quantum chromodynamics. The present limitations of such scaling comparisons are discussed.

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Measurement of J/psi and psi' suppression in p A collisions at 800-GeV/c.

The NuSea collaboration Leitch, M.J. ; Lee, W.M. ; Beddo, M.E. ; et al.
Phys.Rev.Lett. 84 (2000) 3256-3260, 2000.
Inspire Record 507188 DOI 10.17182/hepdata.55127

Measurements of the suppression of the yield per nucleon of J/Psi and Psi' production for 800 GeV/c protons incident on heavy relative to light nuclear targets have been made with very broad coverage in xF and pT. The observed suppression is smallest at xF values of 0.25 and below and increases at larger values of xF. It is also strongest at small pT. Substantial differences between the Psi' and J/Psi are observed for the first time in p-A collisions. The suppression for the Psi' is stronger than that for the J/Psi for xF near zero, but becomes comparable to that for the J/Psi for xF > 0.6.

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Limit on the anti-d / anti-u asymmetry of the nucleon sea from Drell-Yan production

McGaughey, P.L. ; Moss, J.M. ; Alde, D.M. ; et al.
Phys.Rev.Lett. 69 (1992) 1726-1728, 1992.
Inspire Record 344919 DOI 10.17182/hepdata.19848

We present an analysis of 800-GeV proton-induced Drell-Yan production data from isoscalar targets 2H and C, and from W, which has a large neutron excess. The ratio of cross sections per nucleon, R-σW/σIS, is sensitive to the difference between the d¯(x) and u¯(x) structure functions of the proton. We find that R is close to unity in the range 0.04≤x≤0.27, allowing upper limits to be set on the d¯-u¯ asymmetry. Additionally, the shape of the differential cross section m3 d2σ/dxF dm for 2H at xF≊0 shows no evidence of an asymmetric sea in the proton. We examine the implications of these data for various models of the violation of the Gottfried sum rule in deep-inelastic lepton scattering.

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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.

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Nuclear dependence of the production of Upsilon resonances at 800-GeV

Alde, D.M. ; Baer, H.W. ; Carey, T.A. ; et al.
Phys.Rev.Lett. 66 (1991) 2285-2288, 1991.
Inspire Record 315062 DOI 10.17182/hepdata.19910

The yields of the 1S and the sum of the 2S and 3S Υ resonances have been measured for 800-GeV protons incident on targets of H2, C, Ca, Fe, and W. A significant nuclear dependence is seen in the yield per nucleon which, within errors, is the same for the Υ(1S) and Υ(2S+3D) states. A large decrease in the relative yield from heavy nuclei is found for the range xF<0. Significant nuclear dependence is also observed in the pt distribution. Differential cross sections for the Υ(1S) for H2 are presented over the ranges 0.24≤pt≤3.4 GeV/c and -0.15≤xF≤0.5.

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