The Fermilab 15-ft bubble chamber, filled with a heavy neon-hydrogen mix, was exposed to a narrow-band νμ beam. Based on the observation of 830 charged-current νμ interactions, the cross section was found consistent with a linear rise with the neutrino energy in the interval 10 GeV<~Eν≲240 GeV. The average slope was determined to be σνEν=(0.62±0.05)×10−38 cm2 GeV−1.
Measured charged current total cross section.
No description provided.
From 12000 charged-current νμ D events obtained in an exposure of the Fermilab 15-ft bubble chamber to a high-energy wide-band neutrino beam, the absolute neutrino flux is determined using the reaction νμn→μ−p. For the total charged-current cross section, σt=kEν, k=(0.68±0.04±0.10)×10−38 cm2/GeV is obtained for Eν between 10 and 200 GeV. No clear energy dependence of the slope parameter k is observed.
No description provided.
In an exposure of the deuterium-filled 15 ft bubble chamber, σ(νμn→νμX)σ(νμp→νμX) is measured to be 1.01±0.14. The ratios of neutral-current to charged-current cross sections are 0.30±0.03, 0.22±0.03, and 0.49±0.06 for D2, n, and p targets, respectively, which imply values uL2=0.19±0.06 and dL2=0.13±0.04 for the neutral-current chiral couplings. Evidence for both u- and d-quark jets in neutral-current reactions is observed in distributions of energy fraction of the fastest hadron of either charge from each event.
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We present results on inclusive baryon and meson resonance production in\(\bar pp\) interactions at 7.3 GeV/c. Total inclusive and semi-inclusive cross sections are given for Δ(1232),∑*(1385), ϱ0,f andK*±(892) production. For the meson resonances separation into annihilation and non-annihilation components has been made, the annihilation component being dominant at this energy. We find that the energy dependence of inclusive cross sections for ϱ0 production inpp interactions and\(\bar pp\) non-annihilations shows a type of scaling behaviour previously reported for ϕ, ψ, ψ′ and ϒ production inpp interactions.Δ++, ϱ0 andK*± production are studied in terms of Feynmanx,y* andpT2. For the vector mesons we compare they* andx dependences with the predictions of simple quark models.
No description provided.
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RHO0 ANNIHILATION AND NON-ANNIHILATION DATA.
Exposures of the Ne/H 2 filled Big European Bubble Chamber (BEBC) to a dichromatic neutrino (antineutrino) beam produced by 400 GeV protons of the CERN SPS yielded ∼ 3100 events with a negative, and ∼ 1100 with a positive, muon. The neutrino flux is determined from the muon flux in the shielding. Assuming a linear energy dependence of the cross section, the values σ E between 20 and 200 GeV are found to be 0.657 ± 0.012 (stat.) ± 0.027 (syst.) and 0.309 ± 0.009 (stat.) ± 0.013 (syst.) cm 2 (GeV nucleon) −1 , for neutrinos and antineutrinos, respectively. The scaling variable q 2 E decreases significantly with increasing energy both for neutrinos and antineutrinos.
Measured charged current total cross section.
Measured charged current total cross section.
No description provided.
The high mass μ + μ − pairs produced by 280 GeV μ + on a carbon target are studied in a search for the Y production. The high mass continuum in the region 2–18 GeV is interpreted in terms of QED pair production and of μ pairs originating from the decay of hidden and open charm particles as well as of hadrons ( π , K) from deep inelastic interactions. The upper limit for the upsilon production by muons is found to be, at the 90% confidence level, σ γ ·(γ→μ + μ − )<13·10 −39 cm 2 /nucleon.
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The angular distribution and the s dependence of the total cross section for the process e + e − → μ + μ − have been measured using the JADE detector at PETRA. After radiative corrections, a forward-backward asymmetry of −(11.8±3.8) % was observed at an average centre of mass energy of 33.5 GeV. For comparison, an asymmetry of −7.8 % is expected on the basis of the standard Glashow-Salam-Weinberg model.
Best fit to total cross section in energy range.
ANGULAR DISTRIBUTION.
Forward-backward asymmetry within the acceptnce region.
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No description provided.
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From the analysis of 5630 v υ and of 1372 v π charged current interactions, obtained in the BEBC bubble chamber filled with deuterium and exposed to the CERN wide band antineutrino beam, the ratios of cross section on neutron and photon targets have been measured and found to be R σ ν)/σ v p = 0.51 ± 0.01 (±0.03) , and R σ( ν n )/σ( v p ) = 22.2 ± 0.12 (±0.25) The dependence of these ratios on the x scaling variable shows, in a direct way, that the momentum distribution of the majority quark, u p ( x ) = d n ( x ), is broader than that of the minority quark, u n ( x ) = d p ( x ).
No description provided.
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Measurements of pp→μ+μ−+X at s=44 and 62 GeV are compared. The data are taken under identical conditions utilizing clean proton-proton collisions from the CERN intersecting storage rings and confirm scaling to 5%. The observed μ+μ− yield is a factor of 1.6±0.2 larger than estimated from a simple parton model but is consistent with QCD. The pT dependence of the muon pairs agrees well with expectations from QCD.
No description provided.
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