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The angular dependence of the tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen and carbon have been measured. The range of measurements corresponds to the baryonic resonance excitation with masses 2.2--2.6 GeV/c^2. The Ayy data being in good agreement with the previous results demonstrate an approximate $t$ scaling up to -1.5 (GeV/c)^2. The large values of A_y show a significant role of the spin-dependent part of the elementary amplitude of the NN->NN* reaction. The results of the experiment are compared with model predictions of the plane-wave impulse approximation.

The tensor analyzing power A y y in inclusive breakup of 9.0 GeV/c deuterons on hydrogen and carbon has been measured at different emission angles of protons. The data are compared to calculations within the framework of light-front dynamics by using different deuteron wave functions. The results suggest that the relativistic deuteron structure may depend on more than one independent variable.

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 invariant differential cross section, the tensor analyzing power A yy , and the vector analyzing power A y for the reaction 9Be(d, p)X are measured at an initial deuteron momentum of 4.5 GeV/c and a proton detection angle of about 80 mrad. The data obtained for the differential cross section are consistent with the results of measurements at 3.5 and 5.78 GeV/c and a proton emission angle of 2.5°. The values found for the tensor analyzing power A yy are compared with similar data obtained previously for the deuteron-fragmentation process occurring on a carbon target at various values of the initial deuteron momentum and leading to proton emission at zero angle. The data on the differential cross section for the reaction 9Be(d, p)X can be satisfactorily described within the relativistic impulse approximation by using standard deuteron wave functions; however, the approach based on this conceptual framework proves to be inadequate in dealing with data on the tensor analyzing power. These results indicate that it is necessary either to change the method for describing the relativistic deuteron or to take into account additional mechanisms.

The tensor-analyzing power A yy in inclusive breakup of 4.5 GeV/c deuterons on beryllium has been measured at ∼ 80 mr of the detected proton angle. The analyzing power remains positive up to the highest measured momentum of the proton, that is in definitive contradiction with the predictions of the existing models based on the standard deuteron wave functions. The results suggest that the deuteron structure at short distances may depend on more than one independent variable.

The tensor analyzing power Ayy and the vector analyzing power Ay for the inelastic scattering of 4.5-GeV/c deuterons on beryllium nuclei at angle of about 80 mrad are measured in the vicinity of baryon-resonance excitation. These new data, presented as a function of t, comply well with the results of previous 4.5-, 5.5-, and 9-GeV/c measurements at zero angle in overlapping regions of t; all available data are described by a unified dependence on |t| upto about 0.9 (GeV/c)2. The experimental results are compared with the results of calculations performed within the multiple-scattering model and the model involving omega-meson exchange in the t channel.

The behavior of the inclusive cross sections for the cumulative production of π± mesons and protons in pA, DA, and 4HeA interactions is studied versus the atomic mass number of fragmenting nuclei. The primary-beam momenta were 4.5 GeV/c per nucleon. Secondary pions and protons were recorded with a fixed momentum of 0.5 GeV/c at an angle of 120°. Specifically, the experiment explored the fragmentation of D, He, 6Li, 7Li, C, Si, 58Ni, 64Ni, 64Zn, 114Sn, 124Sn, and Pb nuclei. The energy spectra of π+ and π− mesons and protons with momenta in the range 0.3–0.7 GeV/c (the emission angle being 120°) were measured in an 8.9-GeV/c proton beam for Ni, Zn, and Sn isotopes. The special features in the behavior of the cross sections are found and discussed, and a comparison is drawn with the results of other studies.

The tensor analyzing power T20 of the reaction d +A→π − (0°)+X has been measured in the fragmentation of 9 GeV tensor polarized deuterons into pions with momenta from 3.5 to 5.3 GeV/c on hydrogen, beryllium and carbon targets. This kinematic range corresponds to the region of cumulative hadron production with the cumulative variable xc from 1.08 to 1.76. The values of T20 have been found to be small and consistent with positive values. This contradicts the predictions based on a direct mechanism assuming NN collision between a high momentum nucleon in the deuteron and a target nucleon (NN→NNπ).

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 Ayy data for deuteron inclusive breakup off hydrogen and carbon at a deuteron momentum of 9.0 GeV/c and large Pt of emitted protons are presented. The large values of Ayy independent of the target mass reflect the sensitivity of the data to the deuteron spin structure. The data obtained at fixed $x$ and plotted versus Pt clearly demonstrate the dependence of the deuteron spin structure at short internucleonic distances on two variables. The data are compared with the calculations using Paris, CD-Bonn and Karmanov's deuteron wave functions., Comment: 4 pages, 2 figures, talk given at the SPIN2004 Conf., 10-16 Oct. 2004, Triest, Italy

Tensor analyzing power T20 of the reaction dA→π(0°)X was measured in the fragmentation of 9 GeV deuterons into points with the momenta from 3.5 to 5.3 GeV/c at hydrogen, beryllium and carbon targets. This momentum range corresponds to region of cumulative pion production The values of T20 are found to be small and consistent with positive values in contradiction with the Impulse Approximation calculations based on assuming a direct mechanism of pion production (NN→NNπ). New data on tensor Ayy analyzing power for pion production at the non-zero angle (θπ=135,180mr) with pion transverse momenta up to Pt=0.8 GeV/c are presented. Ayy increases with rise of Pt in the cumulative region.

Vector Ay and tensor Ayy analyzing powers of the inelastic scattering of deuterons with the momenta of 4.5 GeV/c on 9Be and 9 GeV/c on 1H and 12C at an angle of ∼80 mr in the vicinity of the excitation of baryonic resonances with masses between 1200 and 2200 MeV/c2 have been measured. The values of parameter Ay suggest that the role of the spin‐dependent part of the NN → NN* elementary processes is significant. The new Ayy data are in good agreement with the previous data at 4.5, 5.5 and 9 GeV/c, obtained at a zero angle, in an overlapping region of t. The results of the experiments are compared with the calculations within the PWIA and ω‐meson exchange model. The data obtained show that polarization observables of (d,d′) reaction in the vicinity of the excitation of baryonic resonances may be used to study their properties.

The data on the tensor analyzing power Ayy in the deuteron breakup reaction on hydrogen and nuclei (9Be and 12C) obtained at 9 and 4.5 GeV/c up to proton transverse momenta of ∼900 MeV/c are presented. The data demonstrate an approximate independence on the A-value of the target, as well as on the deuteron initial momentum, when they are plotted versus variables α and pT, that describe the internal motion of nucleons in the deuteron. The results suggest that a deuteron structure function at short distances may depend on more than one independent variable unlike an ordinary wave function.

Tensor analyzing power T20 in dA→π(θ=0°)X has been measured at fragmentation of 9 GeV deuterons into pions with the momenta from 3.5 to 5.3 GeV/c at H-, Be-, and C-targets. This momentum range corresponds to region of cumulative pion production where the deuteron core structure up to r≃0.4 fm is probed. The values of T20 are found to be small and positive in contradiction with the Impulse Approximation calculations assuming a direct mechanism of pion production on high momentum nucleon in the deuteron (NN→NNπ). In this report we present new data on tensor Ayy analyzing powers at non-zero angles (θ=135,180mr) with pion transverse momenta up to Pt=0.8 GeV/c. Ayy increases with rise of Pt in the cumulative region reaching the magnitude of −0.4 at Pt=0.7–0.8 GeV/c.

Preliminary data on the tensor analyzing power A yy in breakup of 9 GeV/c deuterons on hydrogen and carbon nuclei at secondary proton transverse momenta up to ~ 900 MeV/c are presented. The results suggest that a deuteron structure function at short distances can depend on more than one independent variable unlike an ordinary wave function.

The tensor analyzing power A yy in inclusive breakup of 9 GeV/c deuterons on carbon has been measured at 85 mrad of the detected proton angle using polarized beam of the Synchrophasotron of the Laboratory for High Energies of JINR. The analyzing power A yy remains positive at the highest measured momentum of the proton in definite contradiction with the predictions based on the standard nucleon-nucleon potentials.

Tensor analyzing power T 20 of the reaction d ↑ A → π–(0°)X was measured in the fragmentation of 9 GeV deuterons into pions with momenta from 3.5 to 5.3 GeV/c on hydrogen, beryllium and carbon targets. This momentum range corresponds to the region of cumulative production with the cumulative variable x c from 1.08 to 1.76. The values of T 20 were found to be small and consistent with positive values in contradiction with the predictions based on a direct mechanism assuming N N collision between a high momentum nucleon in the deuteron and a target nucleon (N N → N N π).

The experimental results from a systematic study of cumulative π ± , K ± , p, and d production in the inclusive process B+A→c+X are presented. The beam B was protons, deuterons, helium nuclei, or carbon nuclei with momentum per nucleon equal to 4.5 GeV/ c. The A dependence of the cross sections was measured for these beams for fixed secondary-particle momentum equal to 0.5 GeV/ c and emission angle ϑ=120°. The fragmenting nuclei are D, He, 6 Li, 7 Li, C, Al, Si, Cu, 58 Ni, 64 Ni, 64 Zn, 114 Sn, 124 Sn, and Pb. The energy dependence of the π ± -meson, proton, and deuteron cross sections in the momentum range 0.3–0.7 GeV/ c (ϑ=120°) was measured for 58 Ni, 64 Ni, 64 Zn, 114 Sn, 124 Sn, and Pb nuclei using an 8.9 GeV/ c proton beam. Details of the behavior of the cross sections were found in various nuclear fragmentation regions. The behavior of the exponent of the A dependence of the proton, deuteron, and pion cross sections as a function of the mass number of the nuclei in the primary beam was studied. The results are compared with the data available in the literature. Various models of cumulative particle production in interactions of hadrons and nuclei with nuclei at various beam energies are discussed. Tables of invariant differential cross sections are presented, along with the results of fitting the energy dependence of the cross sections in various representations.