We present an analysis of ππN final states obtained from π−p interactions at 2.26 GeV/c. Strong ρ production is present in both final states. In addition, significant nucleon isobar production is observed. We observed the following cross sections: σ(π−π0p)=3.77±0.13 mb, σ(π−π+n)=5.67±0.17 mb, σ(ρ−p)=2.19±0.09 mb, σ(Δ+(1236)π−)=0.30±0.10 mb, σ(N0(1650)π0)=0.49±0.07 mb, σ(ρ0n)=2.89±0.11 mb, σ(Δ−(1236)π+)=0.11±0.06 mb, σ(N+(1470)π−)=0.24±0.06 mb, and σ(N+(1650)π−)=0.45±0.05 mb. The spin-density matrix elements are determined for the ρ0 by interpreting the ρ0 asymmetry as an interference between the resonant P wave and a T=0 S wave. A search for the ε0 in the π+π−n final state failed to yield a direct observation of this effect.
No description provided.
Results are reported based on a study of π − p interactions at 147 GeV/ c in the FERMILAB 30-inch Proportional Wire Hybrid Bubble Chamber System. We have measured the topological cross sections and separated two-prong elastic and inelastic channels. In addition, we have extracted leading particle cross sections using the increased momentum resolution of the downstream proportional wire chambers. We have compared our results with experiments and predictions of a simple fragmentation hyphothesis.
No description provided.
From a 98000-photograph exposure of the BNL 80-in. deuterium-filled chamber to a 14.6-GeV/c p¯ beam we have extracted those events that fit the channel p¯n→p¯pπ−. The cross section for this channel is measured to be 730 ± 50 μb. The cross section for the reaction p¯n→Δ¯−−(1238)p is determined to be 130 ± 30 μb. Evidence for target dissociation is presented. A comparison with the reaction π−n→π−pπ− at the same energy indicates agreement with factorization.
No description provided.
We determine the ratio of the partial decay width for ψ(3684)→μ+μ− to that for the cascade decay ψ(3684)→ψ(3095)+X to be (1.4 ± 0.3)% and, by direct observation of associated charged particles and γ rays, find the ratio of the partial decay width for ψ(3684)→ψ(3095)+π0π0 to that for ψ(3684)→ψ(3095)+π+π− to be 0.64 ± 0.15.
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
Axis error includes +- 20/20 contribution (UNKNOWN SYSTEMATICAL ERRORDECAY-BR(BRN=J/PSI(3097) --> MU+ MU-, BR=?, C=FOLDED)).
New data from a 600 000 picture exposure of the BNL 31 inch hydrogen bubble chamber to a separated antiproton beam have been analyzed to try to determine if the π + π − π + π − or π + π − π + π − π 0 final states contribute any broad or narrow structure in the T(2190) region. The resonance channel fractions determined by maximum likelihood fits are all consistent with smooth behavior through the T-region and therefore there is no significant evidence that any of these resonance channels contributes to the broad bump in the total cross section. The errors on some of the fractions, however, limit the sensitivity to ∼ 0.5 mb for enhancements in these channels.
RESONANCE CHANNEL PERCENTAGES FROM FIT TO PI+ PI- PI+ PI- FINAL STATE.
RESONANCE CHANNEL PERCENTAGES FROM FIT TO PI+ PI- PI+ PI- PI0 FINAL STATE.
Experimental results on antiproton-proton annihilations at 5 incident momenta in the range 1.22–1.35 GeV/ c into final states with at least one visible K 1 0 meson are presented. Based on a total of 5855 events, cross sections and resonance fractions for all experimentally accessible final states are determined. The total cross section for annihilation into strange particles with at least one visible K 1 0 is 2069 ± 45 ub. Copious resonance production is observed but there is no significant evidence for the formation of a resonance in the s -channel.
No description provided.
RESONANCE FRACTIONS AND CROSS SECTIONS FOR AP P --> KS (K+ PI- + K- PI+).
RESONANCE FRACTIONS AND CROSS SECTIONS FOR AP P --> KS (K+ PI- + K- PI+) PI0.
The results of a study of the reaction π-p→π-π-π+p at2 147 GeV/c carried out at the Fermilab Proportional Wire 30″ Bubble Chamber Hybrid Spectrometer are reported. More than 92% of the cross-section ((670±41) μb) for this reaction is contained in those for proton and pion diffraction dissociation. The cross-sections for pion diffraction events with three-pion invariant mass in given regions are in agreement with values obtained by extrapolation of fits to data at lower incidentpion momenta. ρ0π- events make an important contribution in the A1 and A2 mass regions, and the data are consistent with contributions from f0π- in the A3 mass region. The cross-section for proton diffraction events is in agreement with a smooth extrapolation of the data at lower momentum.
No description provided.
Measurements of the differential cross section for the inclusive production of high-energy π0's are reported for the reactions π±p→π0X at a laboratory momentum of 14 GeV/c. The kinematic range covered, in terms of the Feynman scaling variable x and the transverse momentum P⊥, is 0.25≤x≤1.0 and 0≤P⊥≤0.7 GeV/c. Two spectrometers, both employing large NaI(Tl) crystals, are used to detect the π0's and to identify them with a mass resolution of 17 MeV (full width at half maximum). The results are in accord with the hypothesis of limiting fragmentation, which regards the measured reactions, in the kinematic range covered, as examples of disfavored fragmentation.
No description provided.
No description provided.
The production of KS, Λ, Λ¯, and γ in π−p collisions at 147 GeV/c is analyzed. Cross sections, rapidity, Feynman-x, and pT2 distributions are presented and compared to charged-particle production. The energy dependence of multiplicities in π−p and pp collisions is shown. A new scaling form for the correlation of neutral- and charged-particle multiplicities is presented for compilations of πp and pp data.
Axis error includes +- 0.0/0.0 contribution (?////ERRORS QUOTED ARE MAINLY STATISTICAL BUT INCLUDE CONTRIBUTIONS FROM ESTIMATES OF CONTAMINATION AND OF THE RELIABILITY OF WEIGHTING SCHEMES10 PCT OF ALAMBDA EVENTS COULD BE GAMMA CONTAMINATION, 0.5 PCT OF KS EVENTS COULD HAVE BEEN MISCLASSIFIED AS GAMMA'S).
Axis error includes +- 0.0/0.0 contribution (?////ERRORS QUOTED ARE MAINLY STATISTICAL BUT INCLUDE CONTRIBUTIONS FROM ESTIMATES OF CONTAMINATION AND OF THE RELIABILITY OF WEIGHTING SCHEMES10 PCT OF ALAMBDA EVENTS COULD BE GAMMA CONTAMINATION, 0.5 PCT OF KS EVENTS COULD HAVE BEEN MISCLASSIFIED AS GAMMA'S).
Dimuon production is studied in 217-GeV/c π−-hydrogen and π−-beryllium collisions with a lead-glass array to detect photons associated with the ψ. The ψ−γ mass spectrum shows a 2.6-standard-deviation excess of events above background at ∼3.5 GeV. This excess, if attributed to the decay χ(∼3.5)→ψγ, implies that 0.70±0.28 of the ψ's are produced via radiative decay of one of the χ states.
E*D(SIG)/D(XL) is fitted by (1-X)**POWER.
No description provided.
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