Photoabsorption cross sections in hydrogen and deuterium have been measured from 3.7 to 17.9 GeV. The energy dependences are similar to those of strong-interaction total cross sections, as expected from the vector-meson-dominance model. The magnitude of σT(γp) can be compared with data from γp→ρ0p to determine a γ−p coupling constant, γρ24π=0.37±0.03. This value disagrees with that obtained on the ρ mass shell, and hence there is only qualitative agreement with the vector-meson-dominance model.
Axis error includes +- 1/1 contribution (CORRECTION OF ACCEPTANCE, POSSIBLE LOSSES, ETC).
A high-mass Δ resonance is observed in several final states from π + p interactions at 10.3 GeV/ c . We obtain fitted mass and width values for this structure of 1871 ± 22 MeV and 205 ± 43 MeV, respectively. The branching ratios for decays to π + p, p π + π 0 , n π + π + and Σ + K + are found to be 0.48 ± 0.15, 0.26 ± 0.07, 0.24 ± 0.07 and 0.03 ± 0.01, respectively. The Δϱ, Δω differential cross sections and the ϱ 0 density matrix elements are examined.
DEL(1950B) (OR DEL(1880B)) FITTED WITH BRIET-WIGNER RESONANCE AND POLYNOMIAL BACKGROUND.
No description provided.
No description provided.
The major production channels of four-prong final states resulting from π+p interactions at a center-of-mass energy of 4.5 GeV are studied. In addition to total production cross sections, comprehensive listings of partial and resonance production cross sections are also given for each final state of interest. All final states, including nπ+π+π+π−, are found to exhibit copious resonance production.
PARTIAL CROSS SECTIONS FROM PI+ P --> PI+ P PI+ PI-.
PARTIAL CROSS SECTIONS FROM PI+ P --> PI+ P PI+ PI- PI0.
The pp total cross section difference between pure transverse spin states was measured in the laboratory momentum range 1–3 GeV/ c . Significant differences were found and these differences show striking energy dependence. This structure is in disagreement with the predictions of simple exchange models.
No description provided.
REVISED DATA (J. D. LESIKAR, PRIV COMM, 19 JUN 1981). NOW CORRECTED FOR COULOMB-NUCLEAR INTERFERENCE. IN ADDITION, THE LOWEST MOMENTUM DATA POINT IS NOW KNOWN TO BE IN ERROR.
Cross sections, differential cross sections, single and joint spin-density matrix elements are given for the reactions π+p→(ρ0, ω)Δ++ at 10.3 GeV/c. Correlations between the vector-meson and the Δ++ decay angular distributions are observed. A discussion of the results in terms of particle exchange, SU(3) symmetry, quark additivity, and the equal-phase hypothesis is presented. The amplitudes for the process π+p→ρ0Δ++ are extracted by a model-dependent analysis and compared with current theoretical predictions.
P-WAVE BREIT-WIGNER RESONANCES PLUS BACKGROUND USED WITH SLICE TECHNIQUE.
FROM RESONANCE OVERLAP REGION WITH BACKGROUND SUBTRACTED AND NORMALIZED TO TOTAL CROSS SECTION.
FROM RESONANCE OVERLAP REGION WITH BACKGROUND SUBTRACTED AND NORMALIZED TO TOTAL CROSS SECTION.
Data are presented on the inclusive production of π±, K±, p, and p¯ for π+, K+, and protons incident on nuclear targets at 100 GeV. The results cover the kinematic range 30≤P≤88 GeV/c for Pt=0.3 and 0.5 GeV/c. The observed A dependence of the invariant cross sections exhibits remarkable simplicity, which does not naturally follow from current models of particle production. The results show that the hypothesis of limiting fragmentation can be extended to include collisions with nuclei.
No description provided.
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible.
No description provided.
No description provided.
No description provided.
Neutral kaon to negative pion production ratios fromvp and\(\bar vp\) charged current interactions in BEBC are presented and compared with LUND fragmentation model predictions. Good agreement is obtained with a strangeness suppression factor λ=0.203±0.014(stat)±0.010(sys). No evidence is seen for an energy dependence of λ in our kinematic region.
No description provided.
No description provided.
The difference ΔσT=σ(↓↑)-σ(↑↑) between the proton-proton total cross sections for protons in pure transverse-spin states, was measured at incident momenta 0.8 to 2.5 GeV/c in experiments performed at the Los Alamos Clinton P. Anderson Meson Physics Facility and the Argonne Zero Gradient Synchrotron. In agreement with other data, peaks were observed at center-of-mass energies of 2.14 and 2.43 GeV/c2, where D21 and G41 dibaryon resonances have been proposed.
DATA FROM LAMPF EXPERIMENT.
DATA FROM ARGONNE EXPERIMENT.
None
Pt of the leptons is determined relative to the thrust axis. B-DECAY, C-DECAY, C-SECONDARY and BKG are corresponded to fractions of leptons originationg from primary BQ deacy, primary CQ decay, secondary decay, and from background.
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