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Using BEBC equipped with a hydrogen-filled neon-surrounded track-sensitive target, the charged current cross sections and structure functions of hydrogen and neon targets traversed by the same neutrinos and antineutrinos are compared directly. The measured total cross-section ratios between hydrogen and neon allow precise total cross-section values for hydrogen to be inferred. Using this normalization, the ν and ν hydrogen data are combined and the quark distributions in free nucleons, parametrised as functions of ξ, are extracted. This free-nucleon parametrisation is then compared directly with the neon data in order to measure nuclear effects such as those recently reported by the EMC collaboration. Only small effects are seen, in excellent agreement with recent SLAC data in a more similar A and q2 range. © 1984., 0, SCOPUS: ar.j, info:eu-repo/semantics/published

The results are presented of an analysis of 4709 fully reconstructed K L 0 → π + π − π 0 , observed in a hydrogen bubble chamber. The data fit to a linear π 0 energy spectrum to give a slope parameter g = 0.610 ± 0.022.

K L 0 p interactions were studied in the CERN 2m H 2 bubble chamber in the c.m. energy range 1490–1700 MeV. The experimental details are described. Results are presented on the final states Λπ + , Σ 0 π + and Λπ + π 0 . The effect of these data on a recent partial-wave analysis of the two-body states is examined.

A novel and efficient kinematic method is used to estimate the number of ν τ charged current interactions with E ν > 20 GeV in the BEBC beam dump experiment. The result, −14±12 ν τ events, is consistent with zero. The ratio of D s to D meson production in 400 GeV proton interactions in copper is estimated to be below 0.65 at 90% c.l. The oscillation probability P ( ν e → ν τ ) averaged over the electron-(anti)neutrino spectrum is found to be below 18%. The hypothesis that ν e and ν τ are identical is excluded by about 6 standard deviations. A remarkable event is described: it contains a muon, a high p T photon and a high p T hadron.

Results on the channels K−p → Λ0η0, Λ0π0, Σ0π0, Λ0π0π0 and Σ0π0π0 are obtained in a K−p formation experiment using 1 million photographs taken in a heavy liquid bubble chamber filled with a CF3BrC3H8 mixture. The results are compared with hydrogen bubble chamber (HBC) experiments and with experiments having full or partial gamma-ray detection. Our Λ0π0 and Λ0 + neutral cross section agree with HBC results. Our Σ0π0 cross section does not exhibit a bump at 1670 MeV as previously seen in HBC experiments. Our Λ0π0π0 data are dominated by a Σ(1385)π0 production. Our Σ0π0π0 data is consistent with the presence of some Σ(1405)π0 production.

A study has been made of the individual channels that contribute to the reaction K−p → Λ0 + neutrals in the K− momentum range from 525 to 820 MeV/c. Total cross sections are presented for the K−p → Λ0η0, Σ0Σ0π0, Λ0π0, Σ0π0 and Σ0π0 π0 channels and differential cross sections for K−p → Λ0π0. The data were obtained in a heavy liquid bubble chamber experiment with an average gamma detection efficiency of 70%. Only events with all decay gammas detected were used for analysis. This is the first of a series of papers on this subject and presents the experimental technique in detail.

Particle production by 24 GeV/ c protons from Be, B 4 C, Al, Cu and Pb has been measured. Pion, kaon, proton and antiproton production spectra measured over a range of angles from 17 to 127 mrad and momenta from 4 to 18 GeV/ c are given in a table.

Experimental results on the KL0p → KS0p reaction at 11 laboratory momenta between 300 and 800 MeV/c are presented. The data are used to discriminate among the various sets of phase shifts for K+N scattering in the I = 0 state.