The v and v nucleon total cross-sections have been determined as a function of energy using a sample of 2500 v and 950 v event. The results are compared with predictions of scaling and charge symmetry hypotheses.
Measured charged current total cross section.
Measured charged current total cross section.
None
No description provided.
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The inclusive cross section and the average multiplicity are evaluated for most of the charged ( π ± , p, K ± ) and neutral (γ, π 0 , K 0 , K 0 , Λ, Λ , n ) particles produced in 32 GeV/ c K − p interactions; corresponding results are obtained for each charged topology separately. New results are given for the total charged multiplicity cross sections. The average longitudinal momentum of neutrals is found to be roughly equal to that of charged particles. The π + and π − multiplicity distributions are reconstructed and compared to the π 0 and to the total charged multiplicity distributions.
No description provided.
Axis error includes +- 30/30 contribution (SYSTEMATIC ERROR FOR K0 MULTIPLICITY, WHICH IS EVALUATED FROM 2 ASSUMPTIONS: ALL K0'S COME FROM THE FINAL STATES (N K 2AK PIONS) OR (LAMBDA/SIGMA K AK PIONS) AND CHARGE DISTRIBUTION IN THESE FINAL STATES OBEYS A STATISTICAL ISOSPIN MODEL OF F.CERULUS,NC 19, 528. ALSO ASSUMED THAT SIG(K+)=SIG(KO). VALUES OF SIG(XI-) AND RATIOS SIG(SIGMA+)/SIG(LAMBDA), SIG(SIGMA-)/SIG(LAMBDA) ARE TAKEN FROM 14.3 GEV EXPERIMENT LOUEDEC 76,NC 41A, 166, STATISTICAL ERRORS BEING DOUBLED. FOR ALL ANTIBARYONS ASSUMED THAT SIG(ANTIBARYON)/SIG(BARYON)=SIG(ANTILAMBDA)/SIG(LAMBDA) =0.046+-0.020. SLOW PROTONS WITH PLAB < 1.2 GEV/C ARE IDENTIFIED, AN ESTIMATE FOR FAST PROTON PRODUCTION IS TAKEN FROM FACCINI 77,NP B127, 109).
Axis error includes +- 30/30 contribution (SYSTEMATIC ERROR FOR K0 MULTIPLICITY, WHICH IS EVALUATED FROM 2 ASSUMPTIONS: ALL K0'S COME FROM THE FINAL STATES (N K 2AK PIONS) OR (LAMBDA/SIGMA K AK PIONS) AND CHARGE DISTRIBUTION IN THESE FINAL STATES OBEYS A STATISTICAL ISOSPIN MODEL OF F.CERULUS,NC 19, 528. ALSO ASSUMED THAT SIG(K+)=SIG(KO). VALUES OF SIG(XI-) AND RATIOS SIG(SIGMA+)/SIG(LAMBDA), SIG(SIGMA-)/SIG(LAMBDA) ARE TAKEN FROM 14.3 GEV EXPERIMENT LOUEDEC 76,NC 41A, 166, STATISTICAL ERRORS BEING DOUBLED. FOR ALL ANTIBARYONS ASSUMED THAT SIG(ANTIBARYON)/SIG(BARYON)=SIG(ANTILAMBDA)/SIG(LAMBDA) =0.046+-0.020. SLOW PROTONS WITH PLAB < 1.2 GEV/C ARE IDENTIFIED, AN ESTIMATE FOR FAST PROTON PRODUCTION IS TAKEN FROM FACCINI 77,NP B127, 109).
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.
Two peaks were observed. Mass spectrum was fitted to one and two resonance hypothesis.
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.
No description provided.
No description provided.
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.
No description provided.
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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.
Cross section times branching ratio.
No description provided.
We have studied inclusiveΔ++ (1232),∑+ (1385), and∑− (1385) baryon resonance production inK−p interactions at 32 GeV/c. The inclusive and topological cross sections are estimated and compared with published results at lower energies. No energy variation of the cross section is observed forΔ++ (1232) and only a slight decrease is seen in case of∑± (1385). The production properties are investigated through longitudinal and transverse momentum distributions. TheΔ++ (1232) is dominantly produced in the target fragmentation region. The∑+ (1385) is produced both in the target fragmentation region and in the central region, while the∑− (1385) is predominantly produced in the central region. About 20% of the final state protons are produced via aΔ++ (1232) decay and about 25% of the Λ produced come from the decay of∑+ (1385) and∑− (1385).
No description provided.
No description provided.
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We report final results of a series of measurements of continuum dimuon production in proton-nucleus collisions at Fermilab. New results with 6 times more statistics are included. A full description of the apparatus and methods used in the analysis of this series of measurements is given. The sea quark distribution of the nucleon is determined within the context of Drell-Yan and quantum-chromodynamic description of dilepton production in hadron collisions.
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Charged-current neutrino interactions have been analysed in a sample of pictures from BEBC equipped with a TST. Using a method independent of both the neutrino flux and nuclear interaction corrections, the ratio R = σ n / σ p has been measured. The result is R =1.98±0.19 for the ratio of total cross sections. Bjorken x distributions for proton and neutron targets and for u and d quarks are compared.
No description provided.
No description provided.
No description provided.