[en] The inclusive production of neutral kaons is studied in K⁺ p and π⁺ p interactions at 250 GeV/c. Total and semi-inclusive cross sections and average kaon multiplicities are presented and compared with the data at lower energies. The longitudinal and transverse momentum distributions and their energy dependence are analyzed. The results are interpreted in the framework of recent parton models. (orig.)

[en] An analysis is presented of the rapidity and transverse momentum distributions and of the nuclear stopping power in collisions of π⁺ and K⁺ mesons with Al and Au nuclei at 250 GeV/c. The experimental results are compared to predictions of the additive quark model and the dual parton model. The AQM offers an overall consistent description of the data in this experiment. The DPM reproduces reasonably well the rapidity spectra in the central and projectile fragmentation regions, but fails to describe the nuclear stopping power. (orig.)

[en] Inclusive data are presented on ρ⁰, ρ⁺ and ω produced in K⁺p interactions at 250 GeV/c, for ρ⁺ and ω for the first time in a K⁺p experiment. In the forward CM hemispere, the ρ⁺, ρ⁰ and ω differential production rates are equal within errors, and remarkably similar to muon-inelastic scattering data on ρ⁰ and ω at 280 GeV/c. (orig.)

[en] The negative binomial distribution (NBD) is fitted to all charged and to negative particle multiplicity distributions in restricted rapidity intervals, both in the forward and backward c.m. hemispheres of positive meson interactions on Al and Au nuclei. For negative particle multiplicity distributions, the NBD parameters are also determined as a function of n_g, the number of grey tracks, corresponding to varying number of intranuclear collisions. The data are interpreted in terms of the clan picture of Giovannini and Van Hove and compared to the MCMHA and Fritiof models. Both models reproduce quite well the global multiplicity distributions, but not when sub-samples are considered with fixed number of grey tracks. Regularities are better visible on the parton than on the particle level. (orig.)

[en] We present data on the production of the baryons Λ, anti Λ, p and of the baryon resonances Σ^*+(1385) and Δ⁺⁺(1232) in K⁺p and π⁺p interactions at 250 GeV/c. Results are given on total and semi-inclusive cross sections, Feynman-x spectra, transverse momentum distributions and Λ polarization. The data are compared with measurements at lower energies, with deep inelastic lepton nucleon data and with predictions of quark-parton models. The models underestimate Λ production in the central c.m. region, a feature also seen in recent heavy-ion data. This failure can be cured in JETSET 6.3 by adjustment of the di-quark break-up probability. (orig.)

[en] We report on a study of ρ⁰, ρ⁺, ω, anti K^*0(892) and K^*0(892) inclusive production in π⁺p interactions at 250 GeV/c, for ρ⁺, anti K^*0(892) and K^*0(892) for the first time in a π⁺p experiment. The data are compared with K⁺p data in the same experiment, with results of other experiments and with quark-parton models. Interesting differences are found between ρ^+,0 and ω production. (orig.)

[en] Intermittent behaviour is observed in π⁺p and K⁺p collisions at 250 GeV/c. It is stronger there than in O¹⁶ emulsion, but weaker than in e⁺e^- collisions. A jet cascading mechanism is, therefore, the most likely interpretation. Presently used fragmentation models do not (fully) reproduce the effect, suggesting that an improvement of the hadronization picture is needed. (orig.)

[en] Density fluctuations are studied in rapidity, pseudo-rapidity and azimuthal angle, as well as in two-dimensional distributions in rapidity and azimuthal angle. Evidence for intermittency, i.e. rise of factorial moments with increasing resolution, is found in all four distributions. Intermittency is stronger in two dimensions than in one, but the difference is smaller than would be expected from the production of 'pencil jets'. Contrary to what would be expected from Bose-Einstein interference, no increase by a factor 2 is found in slope when the analysis is restricted of particles of identical charge. (orig.)

[en] A detailed analysis of the inclusive production of the vector mesons φ, K^*+,0(892), anti K^*0(892), ρ^+,0, ω and the tensor mesons K₂^*0(1430) and f₂(1270) in K⁺p interactions at 250 GeV/c is presented. The data are compared with results at lower energies and with various quark-parton models. The production of ρ⁰, K^*0(892) and anti K^*0(892) increases production of ρ⁰, K^*0(892) and anti K^*0(892) increases at the same rate as a function of s, is concentrated in the central region and is not reproduced by the models. Production of the tensor mesons f₂(1270) and K₂^*0(1430) is suppressed relative to ρ⁰ and K^*0(892) by a factor of about 3. (orig.)

[en] The average transverse momentum < p_t> has been studied as a function of the charge multiplicity n in π⁺p, K⁺p and pp collisions at 250 GeV/c (√s≅22 GeV) and compared to that at other energies. The effect of cuts in rapidity and p_T is demonstrated. A comparison to currently used low-p_T models shows that the two-chain dual parton model underestimates the experimentally observed correlation at large p_T. The new version of the two-chain LUND-FRITIOF model is better than the first version of this model, but still overestimates the correlation. (orig.)