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Detailed measurements of five-fold differential cross sections and a rich set of vector and tensor analyzing powers of the 2H(d; dp)n break-up process using polarized deuteron-beam energy of 65 MeV/nucleon with a liquid-deuterium target are presented. The experiment was conducted at the AGOR facility at KVI using the BINA 4Pi-detection system. We discuss the analysis procedure including a thorough study of the systematic uncertainties. The results can be used to examine upcoming state-of-the-art calculations in the four-nucleon scattering domain, and will, thereby, provide further insights into the dynamics of three- and four-nucleon forces in few-nucleon systems. The results of coplanar configurations are compared with the results of recent theoretical calculations based on the Single-Scattering Approximation (SSA). Through these comparisons, the validity of SSA approximation is investigated in the Quasi-Free (QF) region., Comment: 33 pages, 30 figures

In the past two decades, several laboratories have produced a large amount of data for cross sections, analyzing powers, and other spin observables from various reactions in the three-nucleon system. The results allow one to arrive at a moderately good description of the data by only using the two-nucleon potentials in Faddeev-type calculations. The remaining discrepancies should, in principle, and aside from Coulomb and relativistic effects, be removed once the effects of three-nucleon forces are implemented. High precision data on elastic and break-up reactions show, however, that even after the inclusion of these effects, the picture is not complete yet and some ingredients are still missing in the calculations.

Observables in proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects. Several facilities, including the KVI, allow a detailed study of few-nucleon interactions below the pion-production threshold exploiting polarized proton and deuteron beams. In this contribution, some recent results are discussed and interpreted exploiting rigorous Faddeev calculations. Furthermore, experimental inconsistencies between two measurements of the cross section in elastic proton-deuteron scattering at 135 MeV/nucleon are reviewed.

Observables in proton-deuteron scattering are sensitive probes of the nucleon-nucleon interaction and three-nucleon force effects. Several facilities, including the KVI, allow a detailed study of few-nucleon interactions below the pion-production threshold exploiting polarized proton and deuteron beams. In this contribution, some recent results are discussed and interpreted exploiting rigorous Faddeev calculations. Furthermore, experimental inconsistencies between two measurements of the cross section in elastic proton-deuteron scattering at 135 MeV/nucleon are reviewed.

In the past few years, a program has been set up at KVI to study the effects of three-nucleon forces in various reactions. Several observables in elastic and break-up channels in proton-deuteron scattering have been measured and compared with state-of-the-art Faddeev calculations using modem two-body forces and a number of three-body forces. For the elastic scattering process, the data-base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break-up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

In the past few years, a program has been set up at KVI to study the effects of three-nucleon forces in various reactions. Several observables in elastic and break-up channels in proton-deuteron scattering have been measured and compared with state-of-the-art Faddeev calculations using modem two-body forces and a number of three-body forces. For the elastic scattering process, the data-base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break-up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

Understanding the few-nucleon system remains one of the challenges in modern nuclear and hadron physics. Observables in few-nucleon scattering processes are sensitive probes to study the two and many-body interactions between nucleons in nuclei. In the past decades, several facilities provided a large data base to study in detail the three-nucleon interactions below the pion-production threshold by exploiting polarized proton and deuteron beams and large-acceptance detectors. Only since recently, the four-nucleon scattering process at intermediate energies has been explored. In addition, there is a focus to collect data in the hyperon-nucleon sector, thereby providing access to understand the more general baryon-baryon interaction. In this contribution, some recent results in the few-nucleon sector are discussed together with some of the preliminary results from a pioneering and exclusive study of the four-nucleon scattering process. Furthermore, this paper discusses the experimental activities in the hyperon sector, in particular, the perspectives of the hyperon program of PANDA., Comment: 9 pages, 4 figures, proceedings of the 21st European Conference on Few Body Problems in Physics, Salamanca, Spain, 30 August - 3 September 2010

In an experiment with a 65 MeV/nucleon polarized deuteron beam on a liquid-deuterium target at KVI, several multi-body final states in deuteron-deuteron scattering were identified. For these measurements, a unique and advanced detection system, called BINA, was utilized. We demonstrate the feasibility of measuring vector and tensor polarization observables of the deuteron break-up reaction leading to a three-body final-state. The polarization observables were determined with high precision in a nearly background-free experiment. The analysis procedure and some results are presented., 9 pages, 9 figures, accepted for publication in Phys. Rev. C

Precision data are presented for the break-up reaction, $^2{\rm H}(\vec p,pp)n$, within the framework of nuclear-force studies. The experiment was carried out at KVI using a polarized-proton beam of 190 MeV impinging on a liquid-deuterium target and by exploiting the detector, BINA. Some of the vector-analyzing powers are presented and compared with state-of-the-art Faddeev calculations including three-nucleon forces effect. Significant discrepancies between the data and theoretical predictions were observed for kinematical configurations which correspond to the $^2{\rm H}(\vec p,^2$He$)n$ channel. These results are compared to the $^2{\rm H}(\vec p,d)p$ reaction to test the isospin sensitivity of the present three-nucleon force models. The current modeling of two and three-nucleon forces is not sufficient to describe consistently polarization data for both isospin states., 4 pages, 3 figures, submitted to PRL

In the past few years, a program has been set up at KVI to study the effects of three‐nucleon forces in various reactions. Several observables in elastic and break‐up channels in proton‐deuteron scattering have been measured and compared with state‐of‐the‐art Faddeev calculations using modern two‐body forces and a number of three‐body forces. For the elastic scattering process, the data‐base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break‐up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

In the past few years, a program has been set up at KVI to study the effects of three-nucleon forces in various reactions. Several observables in elastic and break-up channels in proton-deuteron scattering have been measured and compared with state-of-the-art Faddeev calculations using modem two-body forces and a number of three-body forces. For the elastic scattering process, the data-base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break-up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

In the past few years, a program has been set up at KVI to study the effects of three-nucleon forces in various reactions. Several observables in elastic and break-up channels in proton-deuteron scattering have been measured and compared with state-of-the-art Faddeev calculations using modem two-body forces and a number of three-body forces. For the elastic scattering process, the data-base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break-up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

In the past few years, a program has been set up at KVI to study the effects of three-nucleon forces in various reactions. Several observables in elastic and break-up channels in proton-deuteron scattering have been measured and compared with state-of-the-art Faddeev calculations using modem two-body forces and a number of three-body forces. For the elastic scattering process, the data-base is now large enough to perform a partial wave analysis to provide an unambiguous description of nuclear forces. For the break-up reaction, data are emerging at intermediate energies revealing interesting aspects of nuclear forces.

We report on a measurement of spin-momentum correlations in quasi-elastic scattering of longitudinally polarized electrons with an energy of 720 MeV from vector-polarized deuterium. The spin correlation parameter $A^V_{ed}$ was measured for the $^2 \vec{\rm H}(\vec e,e^\prime p)n$ reaction for missing momenta up to 350 MeV/$c$ at a four-momentum transfer squared of 0.21 (GeV/c)$^2$. The data give detailed information about the spin structure of the deuteron, and are in good agreement with the predictions of microscopic calculations based on realistic nucleon-nucleon potentials and including various spin-dependent reaction mechanism effects. The experiment demonstrates in a most direct manner the effects of the D-state in the deuteron ground-state wave function and shows the importance of isobar configurations for this reaction., 4 pages, 3 figures, submitted to Phys. Rev. Lett. for publication

The performance of a high-density polarized hydrogen/deuterium gas target internal to a medium-energy electron storage ring is presented. Compared to our previous electron scattering experiments with tensor-polarized deuterium at NIKHEF (Zhou et al., Nucl. Instr. and Meth. A 378 (1996) 40; Ferro-Luzzi et al., Phys. Rev. Lett. 77 (1996) 2630; Van den Brand et al., Phys. Rev. Lett. 78 (1997) 1235; Bouwhuis et al., Phys. Rev. Lett. 82 (1999) 687; Zhou et al., Phys. Rev. Lett. 82 (1999) 687) the target figure of merit, ( polarization ) 2 × luminosity , was improved by more than an order of magnitude. The target density was increased by upgrading the flux of nuclear-polarized atoms injected into the storage cell and by using a longer (60 cm ) and colder (∼70 K ) storage cell. A maximal target thickness of 1.2 (1.1)±0.1×10 14 nuclei / cm 2 was achieved with deuterium (hydrogen). With typical beam currents of 110 mA , this corresponds to a luminosity of about 8.4 (7.8)±0.8×10 31 e − nuclei cm −2 s −1 . By reducing the molecular background and using a stronger target guide field, a higher polarization was achieved. The target was used in combination with a 720 MeV polarized electron beam stored in the AmPS ring (NIKHEF) to measure spin observables in electron–proton and electron–deuteron scattering. Scattered electrons were detected in a large acceptance magnetic spectrometer. Ejected hadrons were detected in a single time-of-flight scintillator array. The product of beam and target vector polarization, P e P t , was determined from the known spin-correlation parameters of e ′ p quasi-elastic (or elastic) scattering. With the deuterium (hydrogen) target, values up to P e P t =0.49±0.03 (0.32±0.03) were obtained with an electron beam polarization of P e =0.62±0.04 (0.56±0.03) as measured with a Compton backscattering polarimeter (Passchier et al., Nucl. Instr. and Meth. A 414 (1998) 4988). From this, we deduce a cell-averaged target polarization of P t =0.78±0.07 (0.58±0.07), including the dilution by unpolarized molecules.

A measurement of the analyzing powers for the H-1((d) over right arrow pp)n breakup reaction at 130 MeV polarized deuteron beam energy was carried out at KVI Groningen. The experimental setup covered a large fraction of the phase space. Obtained tensor analyzing powers T-22 for selected kinematical configurations have been compared to theoretical predictions based on various approaches: the rigorous Faddeev calculations using the realistic nucleon-nucleon potentials with and without three nucleon force (3NF) models, predictions of the chiral perturbation theory, and coupled channel calculations with the explicit Delta degrees of freedom. In the presented configurations the results of all predictions are very close to one another and there are no significant 3NF influences. Not all of the data can be satisfactory reproduced by the theoretical calculations.