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A study of spin effects at fragmentation of 9 GeV polarized deuterons into high momentum pions d A → π (θ) X was for the first time performed at Dubna polarized deuteron facility. Large D -state effects were observed at fragmentation of tensor polarized deuterons into cumulative pions at non-zero emission angles.

The tensor analyzing power A yy in inclusive breakup of 9 GeV/c deuterons on carbon has been measured at the detected proton angle of 85 mr. The analyzing power remains positive at the highest measured momentum of the proton in definite contradiction with the predictions of the existing models. The vector analyzing power A y has been obtained simultaneously with A yy .

The new superconducting accelerator Nuclotron have been operated for the first time at 3.8 and 6.2 GeV/c deuteron momentum and the run on the internal target have been carried out in March'94. The various scintillation counters for ΔE-E and time-of-flight (TOF) measurements, the silicon and CsI(Tl) crystal detectors for ΔE-E measurements as well, and the lead glass EM calorimeters were used. The secondary particles γ, π, K, p, d, and t as well as He fragments produced by deuterons on the internal targets were detected and identified relaibly, thus manifestating a broad perspective of the relativistic nuclear physics research on Nuclotron in the nearest future.

The 4π-detector SPHERE for studying multiple particle cumulative production is currently under construction at the Laboratory of High Energies, JINR, Dubna. This paper briefly describes the present status and future developments of the data acquisition system for this setup. A multiprocessor system based on VMEbus will be implemented for parallel readout, event-building, and data preprocessing. A workstation will be used for data analysis and experimental control. The investigation has been performed at the Laboratory of High Energies, JINR.

The semi-inclusive one-particle transverse and longitudinal momenta spectra of π ± mesons have been studied in the centre-of-mass system for π − p interactions at 40 GeV/ c . These data are compared with similar data from pp interactions at 300 GeV/ c and lower energies. Distributions in the variables p T /〈 p T 〉 and p L /〈 p L 〉 reveal scaling properties, which are found to be substantially independent of the nature of the projectile, of the incident energy and of the prong multiplicity. These spectra are reasonably described by universal functions.

The relation is analysed between the Byckling-Kajantie method of generation of peripheral random events and the usual methods of generation of central-interaction events. The way to ameliorate the efficiency of the method is proposed and tested.