New accurate data on the neutron-proton spin-dependent total cross section difference Δ σ L ( np ) at the neutron beam kinetic energies 1.4, 1.7, 1.9 and 2.0 GeV are presented. A number of physical and methodical results on investigation of an elastic np→pn charge exchange process over a few GeV region are also presented. Measurements were carried out at the Synchrophasotron and Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research.

A superconducting magnet system (SMS) for the multicharged ion source DECRIS-SC was designed and manufactured at the Joint Institute for Nuclear Research. Successful tests of the SMS were conducted in late 2003 - early 2004. The peculiarities of this system are stipulated by using of a cryocooler 1 W in power for the cryostabilization of the magnet, and also by a special configuration of the magnetic field demanded for the source of ions. Four coils ensure induction of a magnetic field on the axes of the source of up to 3T (the mirror ratio of ~ 6) which considerably extends possibilities of the ion source from the point of view of producing intense highly charged ion beams. The problem of compensating large forces of interaction between the coils and surrounding iron yoke in this magnet has been successfully solved, and a reliable suspension of the magnet in a cryostat realized. For compounding of the windings working in vacuum at indirect cryostabilization prepreg is used. There has been applied a new technology of the superconducting magnet protection with the help of sectionalization of the windings, using passive elements of the protection based on "cold" diodes and resistances, as well as a new technology of active protection with normal zone detectors and heaters.

A superconducting magnet system (SMS) for the multicharged ion source DECRIS-SC was designed and manufactured at the Joint Institute for Nuclear Research. Successful tests of the SMS were conducted in late 2003 – early 2004. The peculiarities of this system are stipulated by using of a cryocooler 1 W in power for the cryostabilization of the magnet, and also by a special configuration of the magnetic field demanded for the source of ions. Four coils ensure induction of a magnetic field on the axes of the source of up to 3T (the mirror ratio of ~ 6) which considerably extends possibilities of the ion source from the point of view of producing intense highly charged ion beams. The problem of compensating large forces of interaction between the coils and surrounding iron yoke in this magnet has been successfully solved, and a reliable suspension of the magnet in a cryostat realized. For compounding of the windings working in vacuum at indirect cryostabilization prepreg is used. There has been applied a new technology of the superconducting magnet protection with the help of sectionalization of the windings, using passive elements of the protection based on cold diodes and resistances, as well as a new technology of active protection with normal zone detectors and heaters.

New accurate results of the neutron-proton spin-dependent total cross section difference -Deltasigma(L) (np) at the neutron beam kinetic energies 1.4, 1.7, 1.9 and 2.0 GeV are presented. A fast decrease Of -Deltasigma(L)(np) with increasing energy above 1.1 GeV and a structure in the energy dependence around 1.8 GeV, first observed from our previous data, seem to be well pronounced. The -Deltasigma(L) quantities for isosinglet state I = 0, deduced from the measured Deltasigma(L)(np) values and known -Deltasigma(L)(pp) data, are also given. Preparation of the spin-correlation parameters A(ookk)(np) and A(oonn)(np) measurements is in progress. Measurements were carried out at the Synchrophasotron and Nuclotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research, The aims of these studies is to determine for the first time the imaginary and real parts of the np spin-dependent forward scattering amplitudes over energy range of these Dubna accelerators.

New accurate data of the neutron-proton spin-dependent total-cross-section difference Δσ L(np) at the neutron-beam kinetic energies 1.39, 1.69, 1.89, and 1.99 GeV are presented. In general, these data complete the measurements of energy dependence of Δσ L(np) over the Dubna Synchrophasotron energy region. Measurements were carried out at the Synchrophasotron of the Veksler and Baldin Laboratory of High Energies of the Joint Institute for Nuclear Research. The quasi-monochromatic neutron beam was produced by breakup of extracted polarized deuterons. The deuteron (and hence neutron) polarization direction was flipped every accelerator burst. The initial transverse (with respect to beam momentum) neutron polarization was changed to a longitudinal one and longitudinally polarized neutrons were transmitted through the large proton longitudinally polarized target. The target polarization direction was inverted after one to two days of measurements. Four different combinations of the beam and target parallel and antiparallel polarization directions, both oriented along the neutron-beam momentum, were used at each energy. A fast decrease in −Δσ L(np) with increasing energy above 1.1 GeV and a structure in the energy dependence around 1.8 GeV, first observed from our previous data, seem to be well revealed. The new results are also compared with model predictions and with phase-shift analysis fits. The Δσ L quantities for isosinglet state I = 0, deduced from the measured Δσ L(np) values and known Δσ L(pp) data, are also given. The results of the measurements of unpolarized total cross sections σ 0tot(np) at 1.3, 1.4, and 1.5 GeV and σ 0tot(nC) at 1.4 and 1.5 GeV are presented as well. These data were obtained using the same apparatus and high-intensity unpolarized deuteron beams extracted either from the Synchrophasotron or from the Nuclotron.

New results on energy dependence of the DeltasigmaL(np) over a GeV energy region are presented. Measurements of the np spin dependent total cross section difference DeltasigmaL(np) were carried, out. at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. A quasi-monochromatic neutron beam was produced by break-up of accelerated and extracted polarized deuterons. The neutrons were transmitted through a large proton polarized target. The values of DeltasigmaL were measured as a difference between the np total cross sections for parallel and antiparallel beam and target polarizations, both oriented along the beam momentum. In the 2001 data taking run the DeltasigmaL(np) value were measured at 1.4, 1.7, 1.9 and 2.0 GeV: A fast decrease of DeltasigmaL (np) with increasing energy above 1.1 GeV, as it was first seen from our previous data, was confirmed. The obtained results are also compared with model prediction's and with the phase shift analysis fits. The investigations are carrying out within a program of the "DELTA-SIGMA experiment" project. The aim of these studies is to obtain the values of imaginary and real parts of the spin-dependent forward np-scattering amplitudes over the energy range of 1.2-3.7GeV for the first time.

New results on energy dependence of the Deltasigma(L)(np) over a GeV energy region are presented. Measurements of the np spin-dependent total cross section difference Deltasigma(L)(np) were carried out at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. A quasi-monochromatic neutron beam was produced by break-up of accelerated and extracted polarized deuterons. The neutrons were transmitted through a large proton polarized target. The values of Deltasigma(L) were measured as a difference between the np total cross sections for parallel and antiparallel beam and target polarizations, both oriented along the beam momentum. In 2001 data taking rim the Deltasigma(L)(np) value were measured at 1.4, 1.7, 1.9 and 2.0 GeV. A fast decrease of Deltasigma(L)(np) with increasing energy above 1. 1 GeV, as it was first seen from our previous data, was confirmed. The obtained results are also compared with model predictions and with the phase shift analysis fits. The investigations are carrying out under a program of the "DELTA-SIGMA experiment" project. The aims of these studies are to obtain the values of imaginary and real parts of the spin-dependent forward np-scattering amplitudes over the energy range of 1.2-3.7 GeV for the first time.

Preliminary results of the Δσ L ( np ) at 1.4, 1.7, 1.9 and 2.0 GeV are presented. They were obtained during the two data-taking runs at the JINR Dubna Synchrophasotron in 2001 and complete the existing data above 1.1 GeV. The data analysis is in progress. The aim of the present studies is to determine the imaginary and real parts of the np spin-dependent forward scattering amplitudes over this energy range.

New data on the spin-dependent np observables measured with quasi-monochromatic polarized neutron beam in the energy region from 1.2 to 3.7 GeV are presented. Further measurements of np scattering observables using the JINR LHE polarization facility (longitudinal and transverse polarized neutron beams and a polarized proton target) are discussed. The aim of these studies is to determine the imaginary and real parts of the forward scattering amplitudes for np and for isospin I=0 systems above 1.1 GeV.

New results for the np spin-dependent total cross section difference Δσ p ( np ) at neutron beam kinetic energies of 1.59, 1.79 and 2.20 GeV are presented. Measurements of the Δσ p ( np ) energy dependence were carried out at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. The values of Δσ L were measured as a difference between the np total cross sections for parallel and antiparallel beam and target polarizations, both oriented along the beam momentum. A fast decrease of Δσ p ( np ) with increasing energy above 1.1 GeV, as it was first seen from our previous data, was confirmed. The new results are also compared with model predictions and with the phase shift analysis fits. The Δσ L quantities for isosinglet state I=0, deduced from the measured values of Δσ p ( np ) and known Δσ p ( pp ) data, are given.

A movable polarized proton target is planned to be installed in polarized beams of the Synchrophasotron-Nuclotron complex in order to carry out a spin physics experimental program at Dubna. The project is described and the first proposed experiments are discussed.

A description of the recently installed mouable Polarized Proton Targe (MPT) at the JINR in Dubna is described. This target was acquired from Fermilab. The physics program based on the MPT at Dbna is outlined. (AIP)