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The spin transfer from vertically polarized beam protons to Λ or Σ hyperons of the associated strangeness production p → p → pK + Λ and p → p → pK 0 Σ + is described with the depolarization coefficient D NN . As the polarization of the hyperons is determined by their weak decays, detectors, which have a large acceptance for the decay particles, are needed. In this paper a formula is derived, which describes the depolarization coefficient D NN by count rates of a 4π detector. It is shown that formulas, which are given in publications for detectors with restricted acceptance, are specific cases of this formula for a 4π detector. [ABSTRACT FROM AUTHOR]

Abstract: Modern nucleon-nucleon interaction models can be probed quantitatively in the three-nucleon (3N) environment by comparing predictions based on rigorous solutions of the Faddeev equations with the measured observables. Proper description of the experimental data can be achieved only if the models are supplemented with additional dynamical ingredients: subtle traces of suppressed degrees of freedom, e_ectively introduced by means of genuine three-nucleon forces and e_ects of the Coulomb force. As an example of precision studies of 3N system dynamics, new generation measurements of the 1H(∼d,pp)n breakup reaction at 130 MeV are considered. Large sets of high accuracy, exclusive cross-section and analyzing power data acquired in these projects contribute significantly to constrain the physical assumptions underlying the theoretical interaction models. Comparisons of the cross-section data with the predictions using nuclear interactions generated in various ways, allowed to establish importance of including both, the 3N and the Coulomb forces to strongly improve description of the whole data set. Discrepancies observed in reproducing the analyzing power data hint at still persisting incompleteness of modeling the 3N system interaction dynamics. [Copyright &y& Elsevier]

Abstract: The proton analyzing power in carbon has been measured for energies of 82–217MeV and proton scattering angles of 5–. The measurements were carried out using polarized protons from the elastic scattering reaction and the Focal Plane Polarimeter (FPP) in Hall A of Jefferson Lab. A new parameterization of the FPP p–C analyzing power was fit to the data, which is in good agreement with previous parameterizations and provides an extension to lower energies and larger angles. The main conclusions are that all polarimeters to date give consistent measurements of the carbon analyzing power, independently of the details of their construction and that measuring on a larger angular range significantly improves the polarimeter figure of merit at low energies. [Copyright &y& Elsevier]

Abstract: Direct nuclear reactions and are described in the framework of three-body Faddeev-type equations. Differential cross section and analyzing powers are calculated using several optical potential models and compared with the experimental data. Quite satisfactory agreement is found except for few systematic discrepancies. [Copyright &y& Elsevier]

Abstract: We report on a determination of the analyzing power in the reaction studied with the TOF spectrometer located at the COSY-accelerator (Forschungszentrum Jülich, Germany). This spectrometer is very well suited for polarization measurements due to its rotational symmetry and full coverage of the azimuthal angle. For a beam momentum of corresponding to an excess energy of is found to be compatible with zero. [Copyright &y& Elsevier]

Abstract: The degree of linear polarization of a coherent bremsstrahlung (CB) was measured using an azimuthal asymmetry of incoherent pair production. The measurement was carried out in the -2 photon beam line of the Yerevan synchrotron, using a 2.55GeV electron beam and a diamond radiator oriented to position the primary coherent peak in the interval 0.9–1.1GeV. The polarization at the peak was measured to be , in good agreement with the value computed from CB spectral shape analysis. [Copyright &y& Elsevier]

Abstract: The elastic and inelastic proton scattering on nuclei are studied in a folding model formalism of nucleon–nucleus optical potential and inelastic form factor. The DDM3Y effective interaction is used and the ground state densities are obtained in continuum Skyrme-HFB approach. A semi-microscopic approach of collective form factors is done to extract the deformation parameters from inelastic scattering analysis while the microscopic approach uses the continuum QRPA form factors. Implications of the values of the deformation parameters, neutron and proton transition moments for the nuclei are discussed. The p-analyzing powers on nuclei are also predicted in the same framework. [Copyright &y& Elsevier]

Abstract: The angle-averaged effective analyzing powers, , for proton–carbon inclusive scattering were measured as a function of the kinetic energy of protons in a double scattering experiment. The measurements were performed in the kinetic energy range of 44.8–136.5MeV at the center of 1–5cm thick graphite analyzers using a polarized proton beam on a film or liquid hydrogen serving as target for the primary scattering. These data can be used for measuring the polarization of protons emerging from other reactions such as . [Copyright &y& Elsevier]

Abstract: We measured the analyzing power and the efficiency of a neutron polarimeter at the Saturne National Laboratory in France with central energies of the neutron beam of , and 1057MeV. This polarimeter was a prototype designed to measure , the neutron electric form factor, at the Thomas Jefferson National Accelerator Facility. [Copyright &y& Elsevier]

Abstract: To directly measure the linear polarization of coherent bremsstrahlung (CB) photons with a peak energy of 1GeV at the Yerevan synchrotron, a simple polarimeter is proposed based on a pair spectrometer equipped with two hodoscopes of scintillating counters positioned above and below of the median plane, configured to detect symmetric pairs produced in an amorphous target. Monte Carlo calculations show that the use of a vertical slit collimator at the entrance of the magnet improves both the analyzing power and the energy resolution. The values of the analyzing power for various atomic form factors of the target (the of aluminum) reach a 0.25–0.28 with expected yields of useful events on the level of a few Hz at nominal operating intensity. [Copyright &y& Elsevier]

Abstract: We report a new measurement of analyzing powers for the reaction one charged particle +X, at proton momenta of 1.75, 3.8, 4.5 and . These results extend the existing data basis, necessary for proton polarimetry at intermediate energy, and confirm the feasibility of a large acceptance polarimeter based on this process. Particular attention was devoted to the investigation of the optimal target thickness and of the useful angular range. The experiment is performed at the accelerator complex of the JINR-VBLHE (Dubna). [Copyright &y& Elsevier]

Polarimeters with thick targets are a tool to measure the proton polarization. However, the question about the optimum target thickness is still the subject of discussion. An attempt to calculate the common parameters concerning this problem, in a few GeV region, is made in this paper. [Copyright &y& Elsevier]

We report on a microscopic Refined Resonating Group Model (RRGM) calculation of scattering of p off 3He employing the Argonne-v14 and the Bonn nucleon–nucleon potentials without three-nucleon forces at low energies up to 30 MeV. The calculated phase shifts verify the well-known proton analyzing power Ay problem. We demonstrate that with corrected 3P2 phase shifts experimental differential cross-section and analyzing power data can be explained. [Copyright &y& Elsevier]

The vector polarization of the deuteron beam of the JINR Synchrophasotron (2.5⩽Pd⩽9.0 GeV/c) was measured and monitored by the pp beam polarimeter. Considering the deuteron beam as a beam of weakly bound protons and neutrons, the asymmetries of scattering of protons from deuterons on thin polyethylene and carbon targets were determined. The polarimeter is described, and the values of the vector polarization of the deuteron beam and of the CH2 analyzing power are given. [Copyright &y& Elsevier]

For (e→,e′p→) experiments the 3-spectrometer setup of the A1 collaboration at MAMI has been supplemented by a focal plane proton-polarimeter. To this end, a carbon analyzer of variable thickness and two double-planes of horizontal drift chambers have been added to the standard detector system of Spectrometer A. Due to the spin precession in the spectrometer magnets, all three polarization components at the target can be measured simultaneously. The performance of the polarimeter has been studied using elastic p(e→,e′p→) scattering. [Copyright &y& Elsevier]

The Polarized Atomic Hydrogen Gas Jet Target polarimeter (HJET) is operated at the Relativistic Heavy Ion Collider (RHIC) since 2004 to measure the absolute polarization of each colliding proton beam. Polarimeter detectors and data acquisition were upgraded in 2015 to increase the solid angle, energy range, and to improve the energy and time resolution. These upgrades along with an improved beam intensity and polarization allowed us to greatly reduce the statistical and systematic errors for the proton polarization measurements in RHIC Runs 15 ( E beam = 100 GeV) and 17 (255 GeV). For a typical 8 h RHIC store, the measured proton beam average polarization was about P beam ∼ 55 ± 2. 0 stat ± 0. 3 syst %. The elastic pp analyzing power, A N (t) ∼ 0. 04 , was determined with a precision of about | δ A N (t) | ∼ 0. 0002 in the momentum transfer squared range 0. 001 < − t < 0. 020 GeV 2 . In this paper we present a detailed systematic error analysis of the polarization measurements at HJET. Perspectives of using the HJET based absolute polarimeters in the future Electron Ion Collider (EIC) will be also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Particles scattered off the nuclear target acquire a polarization if the nuclei have a non-zero analyzing power. This effect is enhanced when particles traverse a bent crystal. Such an enhancement under certain assumptions allows one to measure the analyzing power at a level of 10−4 at the square of transfer momentum |t|<10−5 (GeV/c)2. If it happens also that the analyzing power is big enough, then one can get a beam polarization of more than 50% after extraction of the primary beam with the bent crystal. [Copyright &y& Elsevier]