The intermediate and forward gamma detectors of EHS are used to reconstructπ°'s produced by 360 GeV/cpp interactions in the Rapid Cycling Bubble Chamber (RCBC). Using thepp forwardbackward symmetry, the inclusiveπ° production cross section is obtainedσπ°=(132±11) mb. The averageπ° multiplicity is determined as a function of the charged particle multiplicity. The (1−x) dependence is given for differentpT regions.
No description provided.
No description provided.
Axis error includes +- 4/4 contribution.
We present an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV. The forward-backward charge asymmetry of the μ pairs was measured to be −0.098±0.023±0.005. The data were found to agree well with the standard theory of electroweak interaction giving sin2θW=0.27±0.07. The leptonic weak couplings were determined to begv=0.000±0.170 andgA=−0.481±0.055. The data were also used to investigate a class of composite models for leptons.
No description provided.
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The inclusive production of π± andK± mesons and of protons and antiprotons ine+e− annihilation has been measured at c.m. energies ofW=14, 22 and 34GeV. Using time of flight measurements and Cerenkov counters the full momentum range has been covered. Differential cross sections and total particle yields are given. At particle momenta of 0.4 GeV/c more than 90% of the charged hadrons are pions. With increasing momentum the fraction of pions among the charged hadrons decreases. AtW=34 GeV and a momentum of 5 GeV/c the particle fractions are approximately π±:K±:p,\(\bar p = 0.55:0.3:0.15\). On average an event atW=34 GeV contains 10.3±0.4π±, 2.0±0.2K± and 0.8±0.1p,\(\bar p\). In addition, we present results on baryon correlations using a sample of events where two or more protons and/or antiprotons are observed in the final state.
Axis error includes +- 0.0/0.0 contribution (?////EXCEPT OVERALL NORMALIZATION).
Inclusive K0K¯0, Λ0, and Λ¯0 cross sections have been determined using a 292-event/mb exposure of the hydrogen-filled 15-foot bubble chamber at Fermilab. From the invariant-mass distributions of V0π± pairs we find that σ(K*±(890))=4.4±1.4 mb, σ(Σ*±(1385))=0.54±0.40 mb, and σ(Σ¯*±(1385))=0.45±0.34 mb. It is estimated that 0.32 ± 0.11 of K0K¯0's, 0.21 ± 0.16 of Λ's, and 0.96 ± 0.75 of Λ¯'s originate from decays of K*(890) and Σ*(1385), respectively.
No description provided.
No description provided.
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We report on results of η-electroproduction in the resonance region at momentum transfers ofQ2=2 GeV2 and 3 GeV2. The differential cross sections obtained in the region of the second nucleon resonance strongly support the dominance of theS11(1535) in this channel. The total transverse virtual photoproduction cross section of theS11(1535) shows a flatQ2-dependence ∼e−0.39·Q2. Comparison with the total resonant γvp cross section in the second resonance region aroundW=1.5 GeV shows that theD13(1520) production decreases much faster (∼e−1.6·Q2). The data are not compatible with the simple harmonic oscillator quark model with spin and orbit excitation of a quark only.
No description provided.
No description provided.
No description provided.
We report on a measurement of the differential cross sections of inclusive$K^{\pm}_{890}$production in$\sigma^-, pi^-$and ne
The production cross sections for K*+- per nucleus and per nucleon for the SIGMA- beam.
The production cross sections for K*+- per nucleus and per nucleon for the PI- beam.
The production cross sections for K*+- per nucleus and per nucleon for the NEUTRON- beam.
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Total inclusive production cross sections for the SIGMA- beam on the Coppertarget.
Total inclusive production cross sections for the SIGMA- beam on the Carbontarget.
Total inclusive production cross sections per nucleon for the SIGMA- beam, and the exponent in the cross section parametrization of the form A**POWER.
The differential cross sections for antiproton elastic scattering on 4 He at 192.8 MeV/ c are measured. The annihilation cross section σ a = (377.6 ± 8.0) mb, the elastic cross section σ el = (206.3 ± 6.6) mb and the total p 4 He interaction cross section σ tot = (583.9 ± 10.4) mb are determined. The ratio of the real to imaginary part of the forward p 4 He amplitude is found: π =−0.17± 0.33 0.24 . Partial wave analysis reveals that the S, P and D waves are essential in this energy region.
Charged prong multiplicity distributions in pbar HE annihilation.
Mean charged particle multiplicity in pbar HE4 annihilations.
No description provided.
Results are presented for six nuclei from Be to Pb on the structure function ratios F 2 A / F 2 C ( x ) and their A dependence in deep inelastic muon scattering at 200 GeV incident muon energy. The data cover the kinematic range 0.01 < x < 0.8 with Q 2 ranging from 2 to 70 GeV 2 . The A dependence of nuclear structure function ratios is parametrised and compared to various models.
Additional normalisation error of 0.002 in the ratio.
Additional normalisation error of 0.002 in the ratio.
Additional normalisation error of 0.003 in the ratio.
Three narrow peaks with masses 1632 ± 15, 1700 ± 15 and 1748 ± 15, reffered to as R 1 , R 2 and R 3 , have been observed in missing-mass spectrometer runs at incident pion momenta of 7 and 12 GeV/ c and a mass-resolution of ± 15 MeV. One-peak hypothesis gives a confidence level P ( χ 2 )=0.8%; the three-peak one gives P ( χ 2 )=60%. Statistical significance for R 1 , R 2 and R 3 is, respectively, 3.8, 6.6 and 6.1 standard deviations from the highest background line. R 1 and R 2 decay into one and three, while the R 3 decays mainly into three charged particles. Their physical widths are compatible with zero, with upper limits of the order of Γ ⩽30 MeV.
No description provided.
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