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In the present article, ion-beam lithography in ion-exchanged glasses is used as a method for the fabrication of miniaturized phase optical diffractive elements. It is established that, as a result of the interaction of a low-energy (∼ 40 keV) He+ ion beam with silver-ion-exchanged glasses, the index of refraction of interacted area increases. In the interacted areas of the samples, the formation of neutral silver nanoparticles leads to an increase in the index of refraction. This paves the way to employ such material to produce optical phase diffractive elements such as slits, gratings, or Fresnel’s zone plates. It is found that a remarkable dispersion for the index of refraction (n = n(λ)) gives rise to the dependence of diffraction efficiency of produced elements to the wavelength of the probe beams. The produced elements are of good quality, optically effective, chemically stable, waterproof, and scratch resistant.

In the present work, interaction of a low-energy (~ 40 keV) He+ ion beam with silver-ion-exchanged glasses is studied. It is found that the interaction leads to increase of index of refraction and optical density of the interaction area of the samples, and at the same time, results in quenching of luminescence radiation of the interacted area on the samples. A remarkable dispersion for the index of refraction (n = n(λ)) is observed. Maximum change in the index of refraction occurs for the wavelength very close to the wavelength of the red-shifted surface plasmon resonance of the silver nanoclusters embedded in the glass matrix. Photoluminescence spectra studies show that interaction of silver-ion-exchanged glasses with low-energy He+ beam results in reduction of ionic silver clusters to the neutral ones, which is accompanied with increase of the index of refraction. That is, the produced neutral silver nanoparticles increase the index of refraction of the interacted area on the samples. Such manipulation of the index of refraction has potential for manufacturing miniaturized phase optical diffractive elements.

We present measurements of differential cross sections and analyzing powers for the elastic 2H(~d; d)d scattering process. The data were obtained using a 130 MeV polarized deuteron beam. Cross sections and spin observables of the elastic scattering process were measured at the AGOR facility at KVI using two independent setups, namely BINA and BBS. The data harvest at setups are in excellent agreement with each other and allowed us to carry out a thorough systematic analysis to provide the most accurate data in elastic deuteron-deuteron scattering at intermediate energies. The results can be used to confront upcoming state-of-the-art calculations in the four-nucleon scattering domain, and will, thereby, provide further insights in the dynamics of three- and four-nucleon forces in few-nucleon systems., 10 pages, 7 figures

The dependence of the emittance of He+ beam extracted from a cold cathode Penning ion source on source discharge voltage, anode length, and cathode to anode distance was studied. The 2D3V particle-in-cell Monte Carlo simulation technique was utilized to perform the analysis. Different dimensions for components of the ion source such as anode length and cathode to anode distance were considered. The increase in the cathode to anode distance led to a reduction in rms emittance, almost independent of discharge voltage. This study indicated that the rms emittance slightly improves on increasing the anode length.

Detailed measurements of vector and tensor analyzing powers of the ^{2}{\rm H}(\vec d,dp){n} break-up process are presented. The data were obtained using a polarized deuteron-beam with an energy of 65 MeV/nucleon impinging on a liquid-deuterium target. The experiment was conducted at the AGOR facility at KVI using the BINA 4\piπ-detection system. The focus of this contribution is to analyze data of the dddd scattering process in the regime at which the neutron acts as a spectator, which we refer to as the quasi-free (QF) limit. To achieve this, events for which the final-state deuteron and proton are coplanar have been analyzed and the data have been sorted for various reconstructed momenta of the missing neutron. In the limit of vanishing neutron momentum and at small deuteron-proton momentum transfer, the data match very well with measured and predicted spin observables of the elastic deuteron-proton scattering process. The agreement deteriorates rapidly with increasing neutron momentum and deuteron-proton momentum transfer. The results of coplanar configurations in four-body phase space are compared with the results of recent available theoretical calculations based on the Single-Scattering Approximation.

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

Precision measurements of vector and tensor analyzing powers of the $^{2}{\rm H}(\vec d,dp){n}$ break-up process for configurations in the vicinity of the quasi-free scattering regime with the neutron as spectator, are presented. These measurements are performed with a polarized deuteron-beam with an energy of 65 MeV/nucleon impinging on a liquid-deuterium target. The experiment was conducted at the AGOR facility at KVI using the BINA 4$\pi$-detection system. Events for which the final-state deuteron and proton are coplanar have been analyzed and the data have been sorted for various momenta of the missing neutron. In the limit of vanishing neutron momentum and at large deuteron-proton momentum transfer, the data agree well with the measured and theoretically predicted spin observables of the elastic deuteron-proton scattering process. The agreement deteriorates rapidly with increasing neutron momentum and/or decreasing momentum transfer from the deuteron beam to the outgoing proton. This study reveals the presence of a significant contribution of final-state interactions even at very small neutron momenta., Comment: 6 pages, 5 figures, accepted by EPJA

Titanium dioxide thin films were coated on soda-lime glass substrates using spray pyrolysis method with a thickness of 152 ± 10 nm. The films were irradiated with hydrogen ions at room temperature at various beam energies and fluences. Optimized incident beam energy and beam fluence were obtained to improve photocatalytic and hydrophilicity properties of TiO2 thin films by narrowing the band gap. Samples were characterized by scanning electron microscopy to study the surface morphology and by UV–Vis absorption spectroscopy to measure the band gap. The optical band gap of H-doped anatase TiO2 thin films irradiated with hydrogen beam with energies of 2 and 4 keV and a fluence of 1015 ions/cm2 was narrowed from 3.34 eV (before irradiation) to 3.04 and 2.92 eV (after irradiation), respectively. The irradiated sample with energy of 4 keV with a fluence of 1015 ions/cm2 has the best improvement. This is attributed to the contraction of the band gap and to the increase in surface active site. Furthermore, it was observed that photocatalytic and hydrophilicity properties of this sample were improved, as well.

A novel method for measuring nuclear reactions in inverse kinematics with stored ion beams was successfully used to extract the nuclear-matter radius of $^{58}\mathrm{Ni}$. The experiment was performed at the experimental heavy-ion storage ring at the GSI facility using a stored $^{58}\mathrm{Ni}$ beam at energies of 100 and 150 MeV/u and an internal helium gas-jet target. Elastically scattered $\ensuremath{\alpha}$-recoils at low momentum transfers were measured with an in-ring detector system compatible with ultrahigh vacuum. Experimental angular distributions were fitted using density-dependent optical model potentials within the eikonal approximation. This permitted the extraction of the point-matter root-mean-square radius of $^{58}\mathrm{Ni}$ with an average value of 3.70(7) fm. Results from this work are in good agreement with several experiments performed in the past in normal kinematics. This pioneering experiment demonstrates a major breakthrough towards future investigations with far-from-stability stored beams using the present technique.

We have calculated heat capacity of TiO2 nanoparticles in three stable polymorphs by applying size and surface effects on heat capacity of the bulk structure. The size and surface corrections were imposed on the acoustic and optical bulk phonons, separately. The model used in the present work is a simple modification of the model proposed by Wang et al. We applied the modified model to obtain the specific heat capacity of 10-100 nm TiO2 nanoparticles. A very good consistency is observed between the computational and experimental data. Based on the modified model, particles with sizes larger than 70 nm behave like bulk structure. In addition, the heat capacity of particles smaller than 15 nm become independent from their structure details while demonstrating a drastic increase.

The results of a Particle-In-Cell Monte-Carlo Collision simulation of a cold cathode Penning type ion source are presented. The source is designed to generate H− ions through the volume production process. Twenty-one important processes including electron and heavy particle collisions are introduced into the simulation. The main focus was the energy distribution of electrons which has a large effect on the H− production rate in the volume production. The dependence of the energy distribution of electrons on the axial magnetic field was investigated. The large sensitivity of the H− production rate to the energy distribution of electrons was measured. It was observed that for an anode with a 5 mm radius increasing the axial magnetic field in the range of 0.5–1.1 T results in the increase in the H− density almost by a factor of 14. In addition, it was found that the anode with a radius of 5 mm was the most efficient anode in H− production among the anodes with radii from 3 to 6 mm.

High-precision tensor analyzing power T-20 data of the H-1(d, pp)n reaction at 130 MeV beam energy have been determined for 81 kinematical configurations. They are compared to theoretical predictions based on various approaches to describe the dynamics of the three-nucleon (3N) system. The calculations are performed using modern realistic nucleon-nucleon potentials combined with three-nucleon force (3NF) models or with an effective 3NF resulting from the explicit treatment of the Delta-isobar in coupled-channels (CC) calculations. Alternatively, the framework of chiral perturbation theory is used to generate consistent two-nucleon and three-nucleon potentials at the currently numerically attainable order. Results of the CC calculations with the Delta degrees of freedom and including long-range Coulomb force are also shown. In general all predictions are consistent with each other and describe the experimental T-20 results quite well. In a few configurations small inconsistencies between the data and the results of all approaches are observed. Predicted effects of the 3NF are not big and in most cases do not lead to an improved description of the data. The Coulomb force effects are also small in size and often opposite to the effects of TM99 3NF.

Integrated cross-section data for proton-proton bremsstrahlung including the points with the phase-space singularity, which occurs close to the maximum non-coplanarity angle, are presented. A numerical integration of theoretical cross-sections is performed over the non-coplanarity angle to integrate out this singularity. Furthermore, a comparison is made between measured cross-sections and predictions of two soft-photon models. All features observed for the data far from the singularity, including the overestimation of the cross-section by $ \approx$ 30% by the theoretical calculations, emerge as well for the data close to and including the singularity.

Extensive studies of three-nucleon force (3NF) effects in elastic proton-deuteron scattering have been performed at KVI and elsewhere in the past. In the present work, we explored 3NF effects in the break-up scattering process by performing high precision measurement of vector analyzing powers and differential cross sections using a 190 MeV polarized-proton beam on a liquid deuterium target. The experiment was performed by exploiting a new detector called Big Instrument for Nuclear-polarization Analysis, BINA. Its unique design enables coverage of almost the complete reaction phase space. Preliminary differential cross sections and vector analyzing powers are presented and results are compared with state-of-the-art three-nucleon calculations.

We have measured the nuclear-matter distribution of the doubly-magic N = Z nucleus Ni-56 by investigating elastic proton scattering in inverse kinematics. The radioactive beam of Ni-56 was injected and stored in the experimental storage ring (ESR, GSI) and interacted with an internal hydrogen gas-jet target. The high revolution frequency of the ions in the ring enabled a high luminosity, despite the low density of the target being used. This way, measurements at very low momentum transfers became possible. By measuring the energy and the scattering angle of the recoiling protons, we were able to separate the elastic reaction channel from inelastic scattering to the first excited 2(+) state of Ni-56 and deduced the differential cross section of Ni-56 (p, p)(56) Ni. The data were analyzed within the framework of the Glauber multiple-scattering theory in order to extract the nuclear-matter radius and radial matter distribution of Ni-56. Parameterizing the matter distribution with the phenomenological Symmetrized Fermi distribution, a preliminary value of 3.5 fm for the rms matter radius was deduced. This experiment was part of an EXL (EXotic nuclei studied in Light-ion induced reactions at storage rings) campaign at GSI in 2012 and was the first successful investigation of nuclear reactions with a stored radioactive beam ever.

In the first campaign of the exotic nuclei studied with light-ion induced reaction in storage rings (EXL) collaboration at the existing storage ring experimental heavy-ion storage ring (ESR) at Helmholtz Center for Heavy Ion Research (GSI), we performed the first experiments using a stored beam of 58Ni and an internal helium gas-jet target aiming for the investigation of isoscalar giant resonances in inverse kinematics. In this experiment, inelastically scattered recoil particles (at very forward angles, °) were detected with a dedicated setup, including ultra-high vacuum (UHV)-compatible double-sided silicon strip detector (DSSDs). Preliminary results show evidence for the excitation of the isoscalar giant monopole resonance (ISGMR) in the 58Ni nucleus. This opens the opportunity to study in the near future giant resonances also with stored radioactive beams, like 56Ni, and extract important information about the nuclear matter incompressibility. In the present work the current status of the data analysis and results are shown and discussed.

The angle-averaged effective analyzing powers, (A) over barc, 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 44.8-136.5 MeV at the center of 1-5 cm thick graphite analyzers using a polarized proton beam on a CH2 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 H((d) over right arrow,(p) over right arrow-)d. (c) 2006 Elsevier B.V. All rights reserved.

A series of nucleon-nucleon bremsstrahlung (NN gamma) experiments at 190 MeV incident beam energy have been performed at KVI in order to gain more insight into the dynamics governing the bremsstrahlung reaction. After initial measurements wherein the bremsstrahlung process was studied far away from the elastic limit, a new study was used to probe the process nearer to the elastic limit by measuring at lower photon energies. Measured cross sections and analyzing powers are compared with the predictions of a microscopic model and those of two soft-photon models. The theoretical calculations overestimate the data by up to approximate to 30%, for some kinematics.

A cold-cathode Penning ion generator (PIG) has been developed in our laboratory to study the interaction of charged particles with matter. The ignition voltage was measured in the presence of the axial magnetic field in the range of 460-580 G. The performed measurements with stainless steel cathodes were in argon gas at pressure of 4 × 10−2 mbar. A PIC-MCC (particle-in-cell, Monte Carlo collision) technique has been used to calculate the electron multiplication coefficient M for various strength of axial magnetic field and applied voltage. An approach based on the coefficient M and the experimental values of the secondary electron emission coefficient γ, was proposed to determine the ignition voltages, theoretically. Applying the values of secondary coefficient γ leads to the average value of γM(V, B) to be = 1.05 ± 0.03 at the ignition of the PIG which satisfies the proposed ignition criterion. Thus, the ion-induced secondary electrons emitted from the cathode have dominant contribution to self-sustaining of the discharge process in a PIG.

Rich sets of high precision cross sections, vector and tensor analyzing powers for the [Formula: see text] breakup reaction were measured at 130 and 100 MeV beam energy with the use of detection systems covering large parts of the phase space. The cross section data allowed to establish evidences for three-nucleon force contributions and to confirm predictions of sizable effect of the Coulomb force in the breakup reaction. Analyzing power data are generally quite well described by theoretical predictions even with pure nucleon-nucleon interactions. However, in some regions discrepancies has been observed for tensor analyzing powers at 130 MeV.

The investigation of light-ion induced direct reactions using stored and cooled radioactive beams, interacting with internal targets of storage rings, can lead to substantial advantages over external target experiments, in particular for direct reaction experiments in inverse kinematics at very low momentum transfer, q. This new and challenging experimental technique enables high-resolution measurements down to very low q and provides a gain in luminosity from accumulation and recirculation of the stored beams. For performing first experiments of this kind a dedicated experimental setup housing several DSSD (Double-sided Silicon Strip Detector) and Si(Li) detectors for recoil particles, well suited for meeting the demanding UHV (Ultra High Vacuum) conditions of a storage ring, was recently designed, constructed and installed at the internal target of the ESR storage ring at GSI. From the interaction of a stored 56Ni beam with an internal H2 target, good quality differential cross section data for elastic proton scattering, measured with the aim to determine the radial shape of the nuclear matter distribution of 56Ni, were obtained. Preliminary results are presented. Being the first reaction experiment ever performed with a stored radioactive beam on a world-wide scale, this experiment can be considered as a breakthrough for nuclear structure and astrophysics studies, and, in addition, as a successful proof-of-principle of the new experimental concept. In addition, preliminary results from a feasibility study on inelastic α-scattering from 58Ni in inverse kinematics, where it was demonstrated that the Isoscalar Giant Monopole Resonance in 58Ni can be investigated by the present technique down to CM angles below 1 degree, are discussed. Such an experiment, performed in the future with the doubly magic 56Ni, would provide important information on the EOS of nuclear matter.

A series of measurements have been performed at KVI to obtain the vector analyzing power Ay Of the H-2((p) over right arrow, pd) reaction as a function of incident beam energy at energies of 120, 135, 150, and 170 MeV. For all these measurements, a range of upsilon (c.m) from 30 degrees to 170 degrees has been covered. The purpose of these investigations is to observe possible spin-dependent effects beyond two-nucleon forces. When compared to the,predictions of Faddeev calculations, based on two-nucleon forces only, significant deviations are observed at all energies and at center-of-mass angles between 70 degrees and 130 degrees. The addition of present-day three-nucleon forces does not improve the description of the data, demonstrating the still insufficient understanding of the properties of three-nucleon systems.

The European physical journal / Web of Conferences 66, 03093 (2014). doi:10.1051/epjconf/20146603093, Published by EDP Sciences, Les Ulis

21st International School on Nuclear Physics and Applications & the International Symposium on Exotic Nuclei, Varna, Bulgaria, 7 Sep 2015 - 12 Sep 2015; Journal of physics / Conference Series Conference Series 724(1), 012026 - (2016). doi:10.1088/1742-6596/724/1/012026, The EXL project aims to study nuclear structure by direct reactions in inverse kinematics at the storage rings of the future FAIR facility. In this contribution, we present the status of the project: the technical implementation at the ESR at GSI and preliminary results of the EXL campaign in 2012, the first using also a radioactive beam., Published by IOP Publ., Bristol

A cold-cathode penning-type ion source has been developed in our laboratory to study the electric breakdown in this type of sources. The breakdown voltage was measured as a function of axial magnetic field, in the range of 440-600 G, and anode length, in steps of 14, 20, and 24 mm. The measurement was performed with stainless steel cathodes in argon gas at pressure of 4 × 10(-2) mbar. Furthermore, a model was developed to explain the breakdown voltage data. In the construction of the model, the first Townsend coefficient was not directly used to avoid difficulties originating from the non-uniformity of the electric field. The empirical parameters of the model were obtained using the experimental data. The equation γ = c × (E(z)/N)(n), expressing the effective secondary emission coefficient in terms of reduced electric field, which was needed in the modeling process, was inspired from previous works. The parameters c and n were then calculated from the empirical parameters of the model. The n parameter turned out to be 0.59, which differs from the value reported by other authors merely by 1.6%. Three values, 0.010, 0.013, and 0.017 corresponding to the three anodes were obtained for the c parameter. These numbers are in good agreement with 0.01, which has been reported in the previous works. It was also found that the value of n has a decisive impact on the breakdown voltage curve in the high breakdown voltage region.

Differential cross sections of the reaction $p(d,^3{\rm He})\gamma$ have been measured at deuteron laboratory energies of 110, 133 and 180 MeV. The data were obtained with a coincidence setup measuring both the outgoing $^3$He and the photon. The data are compared with modern calculations including all possible meson-exchange currents and two- and three- nucleon forces in the potential. The data clearly show a preference for one of the models, although the shape of the angular distribution cannot be reproduced by any of the presented models., Comment: 6 pages, 6 figures, accepted for publication in EPJA

High-precision data for vector and tensor analyzing powers for the $^{1}\mathrm{H}$$(\mathrm{dP\vec},\mathit{pp})n$ reaction at a 130-MeV deuteron beam energy have been measured over a large part of the phase space. Theoretical predictions based on various approaches to describe the three nucleon ($3N$) system reproduce very well the vector analyzing power data and no three-nucleon force effect is observed for these observables. Tensor analyzing powers are also very well reproduced by calculations in almost the whole studied region, but locally certain discrepancies are observed. For ${A}_{\mathit{xy}}$ such discrepancies usually appear, or are enhanced, when model $3N$ forces, TM99 or Urbana, are included. Problems of all theoretical approaches with describing ${A}_{\mathit{xx}}$ and ${A}_{\mathit{yy}}$ are limited to very small kinematical regions, usually characterized by the lowest energy of the relative motion of the two protons.

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

High precision vector and tensor analyzing powers for the 1H(d, pp)n breakup reaction were measured at 130 MeV beam energy with the detection system covering a large part of the phase space. Results are compared with rigorous theoretical calculations based on realistic nucleon-nucleon potentials, also with so-called three-nucleon force included, as well as on chiral perturbation theory. Theoretical predictions generally describe data quite well although in some regions discrepancies have been observed, what indicates incompleteness of the present-day treatment of the three nucleon system dynamics.

A systematic study of three-nucleon force (3NF) effects in break-up reactions has been carried out at KVI at several energies. In this article, the p + d -> p + p + n reaction with a polarized-proton beam of 190 MeV will be discussed. The experiment was performed by exploiting a new detector called BINA. Some results for high-precision vector analyzing powers and differential cross sections are presented and compared with state-of-the-art Faddeev calculations with or without 3NF.

The three-nucleon system is the simplest non-trivial testing ground in which the quality of modern nucleon-nucleon interaction models, as well as additional dynamical ingredients referred to as three-nucleon forces, can be probed quantitatively by means of a rigorous technique of solving the Faddeev equations. A large set of high precision, exclusive cross-section data for the (1)H((d) over right arrow, pp)n breakup reaction at 130 MeV was obtained at KVI, Groningen. It allowed to establish for the first time a clear evidence of the three-nucleon force contributions to the cross sections of the breakup process and to confirm recent predictions of sizable influences of the Coulomb force in this reaction.

High precision vector Ax,Ay and tensor Axx,Axy,Ayy analyzing powers for the 1H(d,pp)n breakup reaction were measured at 130 MeV beam energy with the detection system covering a large part of the phase space. Results are compared with rigorous theoretical calculations based on realistic nucleon‐nucleon potentials, also with a so‐called three‐nucleon force included, as well as on chiral perturbation theory. Theoretical predictions generally describe the data quite well, but in some regions discrepancies have been observed, which indicate incompleteness of the present‐day treatment of three nucleon dynamics.

The cross section and several spin-dependent observables have been measured with high precision for the reaction H(d,p)d at 90 MeV/nucleon. Several calculations were performed based either purely on two-nucleon potentials or also including three-nucleon potentials (3NP). The cross sections are consistent with all calculations including 3NPs. However, no single calculation reproduces the analyzing powers and spin-transfer coefficients, although some spin observables are reproduced to various degrees by the different calculations. A good understanding of the spin structure of 3NP is still lacking.

High precision cross-section data of the deuteron-proton breakup reaction at 130 MeV deuteron energy are compared with the theoretical predictions obtained with a coupled-channel extension of the CD Bonn potential with virtual Delta-isobar excitation, without and with inclusion of the long-range Coulomb force. The Coulomb effect is studied on the basis of the cross-section data set, extended in this work to about 1500 data points by including breakup geometries characterized by small polar angles of the two protons. The experimental data clearly prefer predictions obtained with the Coulomb interaction included. The strongest effects are observed in regions in which the relative energy of the two protons is the smallest., 9 pages, 3 figures, submitted to Physics Letters B

Vector and tensor analyzing powers of the 1H(d,pp)n breakup process have been measured at the beam energy of 130 MeV. The forthcoming results will be compared with predictions based on various 2N and 3N forces models in quest for a correct structure of the 3NF.

The question, whether the high-quality nucleon-nucleon potentials can successfully describe the three-nucleon system, and to what extent three-nucleon forces (3NFs) play a role, has become very important in nuclear few-body physics. One kinematic region where effects because of 3NFs show up is in the minimum of the differential cross section of elastic nucleon-deuteron scattering. Another observable, which could give an indication about the contribution of the spin to 3NFs, is the vector analyzing power. To investigate the importance of 3NFs systematically over a broad range of intermediate energies, both observables of elastic proton-deuteron scattering have been measured at proton bombarding energies of 108, 120, 135, 150, 170, and 190 MeV, covering an angular range in the center-of-mass system between ${30}^{\ifmmode^\circ\else\textdegree\fi{}}$ and ${170}^{\ifmmode^\circ\else\textdegree\fi{}}$. The results show unambiguously the shortcomings of calculations employing only two-body forces and the necessity of the inclusion of 3NFs. They also show the limitations of the results of the present day models for few-nucleon systems at backward angles, especially at higher beam energies. New calculations based on chiral perturbation theory are also presented and compared with the data at the lowest energy.

Differential cross-sections and proton multiplicities, resulting from the bombardment of 56Fe, 208Pb, and 238U targets by a 190 MeV proton beam were measured for the first time. Data were taken over two different angular ranges 5 $^\circ$ -30 $^\circ$ and 91 $^\circ$ -160 $^\circ$ with two different detection systems. Angular distributions of fast (> 20 MeV) protons are all forward peaked, due to the dominating elastic-scattering contribution. Moreover, the shapes of the distributions are quite independent of the target. The results are compared with modern optical-model predictions and with Intra-Nuclear Cascade (INC) calculations. Reasonable agreement between calculations and experimental data is obtained in the forward angles, but the comparison clearly indicates the need to modify the parameterization of the model at backward angles, where the agreement is rather poor.

Two high-accuracy measurements of cross sections and analyzing powers for the proton-proton bremsstrahlung reaction have been performed at 190 MeV beam energy. These measurements provide not only the most accurate exclusive cross-section and analyzing-power data to date, but also a wide phase-space coverage. Thus, an accurate test of nucleon-nucleon interaction models is made feasible. The experimental setup and the analysis procedure are discussed in detail. Microscopic calculations and calculations based on the soft-photon theorem show deficiencies in explaining the bulk of the data.

The measurement of exclusive deuteron-proton breakup for kinematics covering a large fraction of the available phase space has been performed using 130 MeV deuteron beam. High precision fivefold cross section data in 38 kinematical configurations have been compared to predictions of modern nuclear forces. To this aim the three-nucleon s3Nd Faddeev equations have been solved rigorously using the nucleon-nucleon (NN) potentials AV18, charge-dependent Bonn, Nijm I, and Nijm II alone, and combining them with the 2p-exchange Tucson-Melbourne three-nucleon force (TM 3NF) and with its modified version TM99, more consistent with chiral symmetry. The AV18 potential was also combined with the Urbana IX 3NF. Global comparison of the measured cross sections to pairwise NN force predictions only and with 3NF’s included clearly reveals the presence of 3NF effects. Our study demonstrates the usefulness of the kinematically complete breakup reaction studied in the full phase space to search for 3NF effects.

To investigate the importance of three-nucleon forces (3NF) systematically over a broad range of intermediate energies, the differential cross sections of elastic proton-deuteron scattering have been measured at proton bombarding energies of 108, 120, 135, 150, 170 and 190 MeV at center-of-mass angles between $30^\circ$ and $170^\circ$. Comparisons with Faddeev calculations show unambiguously the shortcomings of calculations employing only two-body forces and the necessity of including 3NF. They also show the limitations of the latest few-nucleon calculations at backward angles, especially at higher beam energies. Some of these discrepancies could be partially due to relativistic effects. Data at lowest energy are also compared with a recent calculation based on \chipt.

A series of measurements have been performed at KVI to obtain the vector analyzing power A(y) of the (2)H(p--,pd) reaction as a function of incident beam energy at energies of 120, 135, 150, and 170 MeV. For all these measurements, a range of theta(c.m.) from 30 degrees to 170 degrees has been covered. The purpose of these investigations is to observe possible spin-dependent effects beyond two-nucleon forces. When compared to the predictions of Faddeev calculations, based on two-nucleon forces only, significant deviations are observed at all energies and at center-of-mass angles between 70 degrees and 130 degrees. The addition of present-day three-nucleon forces does not improve the description of the data, demonstrating the still insufficient understanding of the properties of three-nucleon systems.

Three-nucleon system dynamics can be investigated quantitatively by comparing observables calculated with the use of Faddeev equations with results of precise measurements. Proper description of the experimental data can be achieved only if the dynamical models include, in addition to the nucleon-nucleon interaction, subtle effects of suppressed degrees of freedom, effectively introduced by means of genuine three-nucleon forces. A large set of high precision, exclusive cross-section data for the (1)H(d,pp)n breakup reaction at 130 MeV contributes significantly to constrain the physical assumptions underlying the theoretical interaction models. Comparison of nearly 1,800 cross section data points with the predictions using nuclear interactions generated in various ways, allowed to establish importance of including both, the three-nucleon and the Coulomb forces to significantly improve the description of the whole data set.

We have studied spin observables in the three-body break-up reaction in deuteron-deuteron scattering in the phase-space regime that corresponds to the quasi-free deuteron-proton scattering process with the neutron as spectator. The data are compared to measurements of the elastic deuteron-proton scattering process and state-of-the-art Faddeev calculations. The results for iT(11) and T-22 for the quasi-free scattering data agree very well with previously published elastic-scattering data. A significant discrepancy is found for T-20, which could point to a break-down of the quasi-free assumption. (C) 2013 Elsevier B.V. All rights reserved.