We report measurements at the CERN PS of the production cross section of J/ψ(3.1) by 24 GeV protons on hydrogen, carbon, and tungsten.
No description provided.
ASSUME B.R.(E+E-) =0.069.
We present results of a large-acceptance experiment in which muon pairs were observed in the mass range 0.6 to 6.0 GeV/c2. Emphasis is given to features of the production of Jψ and ψ′(3.7) particles. We find [Bσ]ψ′(3.7)[Bσ]Jψ to be 0.007±0.004 for p-C and 0.018±0.007 for π+-C interactions. Comparison with results from e+e− storage rings indicates that both the Jψ and the ψ′(3.7) are produced strongly rather than electromagnetically in our experiment.
No description provided.
The production of J/ψ by π ± , K ± , p and p¯ incident on tungsten at 39.5GeV/ c beam momentum has been studied. Production of ψ' (3700) by π ± was also observed. The J/ψ relative particle/a ntiparticle cross-sections for x F 0 are σ(σ + ) σ(σ − =( are σ(σ ± )/σ(σ − )=(1.01±0.06), σ(K + )/σ(K) − )=(0.29±0.07) and σ(p) /σ(p¯)= (0.1+-0.03). The small p/p¯ and K + /K − cross-section ratios indicate the importance of valence quarks in the production process.
No description provided.
No description provided.
Invariant mass spectrum of μ + μ − pairs produced by 70 GeV/ c protons in Be target are presented. Distinct enhancements in the mass regions of ϱ, ω mesons, φ meson and J/ψ particle are observed. For J/ψ production x and p ⊥ 2 distributions are given. The total cross section for the reaction p + Be → ( J ψ → μ + μ − ) + … is equal to 9.5 ± 2.5 nb/nucleus .
No description provided.
ASSUME B.R.(MU+MU-) = 0.069.
ASSUME A**(2/3) DEPENDENCE FOR SIGMA.
We report the measurements of the inclusive μ-pair production by 150-GeV protons and π+ mesons on beryllium. Absolute cross sections as well as the Feynman-x and PT dependence are presented in the mass region between 0.211 and 3.5 GeV/c2. Upper limits are also given for the inclusive production of η and ρ′(1600) mesons.
DATA OBTAINED FROM FIGURE BY A.A. LEBEDEV.
DATA OBTAINED FROM FIGURE BY A.A. LEBEDEV.
No description provided.
A detailed study ofJ/ψ hadronic production has been performed in a high statistics experiment (more than 1.5 106J/ψ observed in their dimuon decay mode). Data have been taken with incident π±,K±,p±, on hydrogen and platinum targets, at 150, 200 and 280 GeV/c. We find from the observed nuclear dependance of the cross sections, that about 18% of theJ/ψ are produced diffractively. Using known structure functions of the quarks in the nucleon and in the pion, we derive estimations for the gluon structure functions.
No description provided.
No description provided.
No description provided.
The yield of J/ψ and ψ’ vector-meson states has been measured for 800-GeV protons incident on deuterium, carbon, calcium, iron, and tungsten targets. A depletion of the yield per nucleon from heavy nuclei is observed for both J/ψ and ψ’ production. This depletion exhibits a strong dependence on xF and pt. Within experimental errors the depletion is the same for the J/ψ and the ψ’.
Ratio of heavy nucleus to deuterium yields. A is the mass number of the target nucleus.
Ratio of heavy nucleus to deuterium yeilds. A is the mass number of the target nucleus.
Ratio of heavy nucleus to deuterium yeilds. A is the mass number of the target nucleus.
None
Data is extrapolated to full x range.
Data requested from authors.
Muon-pair production has been measured in pCu, pU, OCu, OU and SU collisions at 200 GeV per nucleon. The cross sections are compatible with the atomic number dependence ( A proj. A targ. ) α where α =0.91±0.04 for the J/ψ resonance and α =1.01±0.04 for muon pairs produced in the mass continuum between 1.7 and 2.7 GeV/ c 2 .
Cross sections fitted with SIG0*(A(P=1)*A(P=2))** ALPHA. ALPHA is coded here as POWER(N=A*A,YN=SIG).
Cross sections fitted with SIG0*(A(P=1)*A(P=2))** ALPHA. ALPHA is coded here as POWER(N=A*A,YN=SIG).
No description provided.
Hadroproduction of the Jψ and ψ′ states has been studied in 300-GeV/c proton, antiproton, and π±Li interactions. Both total and differential cross sections in xF and pT have been measured for the Jψ for the π±, proton, and antiproton interactions. The ratio of ψ′ to Jψ production has been determined for the four types of beam particles.
No description provided.
No description provided.
No description provided.