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Photoproduction of the ω meson on the proton has been experimentally studied near the threshold. The total cross sections are determined at incident energies ranging from 1.09 to 1.15 GeV. The 1/2 and 3/2 spin-averaged scattering length aωp and effective range rωp between the ω meson and proton are estimated from the shape of the total cross section as a function of the incident photon energy: aωp=(−0.97±0.16)+ i (0.07±0.15) fm and rωp=(+2.78±0.61)+ i (−0.01±0.48) fm, which suggests a repulsive force. The real and imaginary parts for aωp and rωp are determined separately for the first time. The details of the analysis and discussions are described in Ref. [1]. [ABSTRACT FROM AUTHOR]

In this study, Co and Al ions co-doped ZnO nanoparticles (Zn(Al, Co)O NPs) were prepared by our original chemical preparation method. The obtained samples prepared by this method, were encapsulated in amorphous SiO2. Xray diffraction (XRD) results showed Zn(Al, Co)O NPs had a single-phase nature with hexagonal wurtzite structure. These particle sizes could be controlled to be approximately 30 nm. We investigate the effect that the increase in the carrier has on the magnetization by doping Al to Co-doped ZnO NPs. The local structures were qualitatively analyzed using X-ray absorption fine structure (XAFS) measurements. [ABSTRACT FROM AUTHOR]

We will measure the X-rays from kaonic 3He 3d → 2p transition with a precision below 2 eV. It can provide crucial information on the kaon-nucleus strong interaction. The experiment (J-PARC E17) will be performed as Day-1, which is one of the first experiments in the J-PARC hadron facility in the year 2011. An overview and the present status of the J-PARC E17 experiment are described. [ABSTRACT FROM AUTHOR]

To form a magnified hard X-ray image with a 50 nm resolution, we have studied total reflection mirror optics with two pairs of elliptical and hyperbolic mirrors, which is called “Advanced Kirkpatrick-Baez system”. A designed optical system has 200x and 300x magnifications in vertical and horizontal directions. Also diffraction limit size in the optical system is 40 nm×45 nm. We fabricated a pair of elliptical and hyperbolic mirrors for horizontal imaging with a figure accuracy of 2 nm using elastic emission machining (EEM), microstitching interferometry (MSI) and relative-angle-determinable stitching interferometry (RADSI). One-dimensional tests for forming a demagnified image of a slit were carried out at an X-ray energy of 11.5 keV at BL29XUL (EH2) of SPring-8. As a result, a shape beam with a FWHM of 78 nm was observed. This demonstrates that we realized one-dimensional Wolter optics that has a spatial resolution of 78 nm. [ABSTRACT FROM AUTHOR]

A gas monitor detector was calibrated to a cryogenic radiometer for measuring the radiant power of EUV-FEL (extreme ultraviolet free electron laser) at the wavelengths of 51 nm and 61 nm. The output signals of the gas monitor detector showed good linearity against the radiant power measured by the radiometer in the range from 6 μW to 160 μW. The calibration coefficients of the gas monitor detector are determined with the relative standard uncertainty of around 5 %. [ABSTRACT FROM AUTHOR]

The dimensional tolerance of spur gear for automobile would be within the range of a several micrometer. Therefore, to manufacture these gears by cold forging, dimensions should be controlled in same range. The dimensional changes by the various forging variables should be analyzed and compensated into the forging tool. CAE would be appropriate for investigating the effects of variables. However, the realistic FE-modeling techniques should be confirmed and used to predict the dimension of forged part in micrometer order. Since the realistic modeling considers elastic characteristics of both workpiece and die and unloading and ejecting stage, 3-dimensional analysis for spur gear may be often facing difficulties in a solving time and convergence. In this study, dimensional changes for cold forged part of spur gear were investigated by experimental and FEM analysis, after FE modeling to get the desirable FEM results had been studied by the closed die upsetting. The dimensional changes of involute curve for spur gear could be analyzed from the FEM results during a whole forging stage. And, they could give an index of modified involute curve of forging tool for improving the gear profile accuracy. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this study, a method was devised for deciding material properties relating to ductile fracture (damage parameters) through a simple experiment. To predict void nucleation, a void nucleation critical strain model was proposed. Gradual changes in the necking shape were measured by using notched round bar tension test using image analysis. From the results, strain and stress history at the necking section were obtained by Bridgman’s correction. From the result, the decision of the ductile damage parameters were carried out on some ductile fracture criteria. Additionally, the relationship between void volume fraction and strain was investigated using an experimental two-step tension test. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

In order to establish technology for future X-ray FEL at 1 Angstrom wavelength region, RIKEN/SPring-8 started SCSS-project in 2002. It is a soft X-ray SASE FEL machine aiming at demonstrating FEL operation below 10 nm wavelength with 1 GeV electron beam. Using the short period in-vacuum undulator and the high gradient C-band main accelerator, the machine becomes compact, and fits within a 100 m long tunnel, so that it was named SCSS: SPring-8 Compact SASE Source. To saturate FEL within 25 m long undulator line, we need a high quality beam: r.m.s normalized emittance should be below 2 π-mm-mrad (r.m.s normalized) with 2 kA peak current. To generate this beam, we are developing a HV pulse gun using thermionic cathode (CeB6 single crystal) and sub-harmonic buncher system. In 2003, we start beam test of HV gun and high power test of the C-band accelerator. The first FEL operation is scheduled in 2006 at 100–10 nm wavelength. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

The output energy and resolving power of a high-resolution monochromator are sensitive to temperature and vibrations of optical elements. Cooling of mirrors and gratings require: (1) to decreasing the velocity of cooling water with sufficient flow rate, (2) positioning devices to avoid distortion by cooling tube, and (3) maintaining an intimate contact with plates for exhausting heat. We have installed a cooling system that fulfills these essential conditions by using InGa in the monochromator of BL27SU, so that its energy drift is decreased to 10 meV for 6 hours. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Refocusing mirrors were designed and equipped in the high-resolution branch of BL27SU in SPring-8. It is required to switch quickly among the three tandem end-stations and achieve a vertical size of less than 10 microns at one experimental station. Two toroidal mirrors and a set of two cylindrical mirrors were employed in order to align them easily. The beam size and photon flux were measured. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have evaluated the characteristics of the mechanically-bent-shaped mirror for x-ray optics by using Long-Trace-Profiler. “Arm Method” mirror bender can control the curvature of the mirror with little effect to the slope error. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

A low-energy radioactive-ion beam separator based on an in-flight technique was developed at CNS, University of Tokyo and was installed at RIKEN. Using the separator, experiments of the elastic resonance scattering of 11C+p, 12N+p, and 23Mg+p were performed to study resonance levels in 12N, 13O, and 24Al, respectively. New information on spin-parities and widths for these levels may help understand stellar (p,γ) reaction rates. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Cross sections and polarization transfer observables in the 16O(p,p′) reactions at 392 MeV were measured at forward angles including 0°. The non-spin-flip (ΔS = 0) and spin-flip (ΔS = 1) strengths in transitions to several discrete states and broad resonances in 16O were extracted using a model-independent method. The giant resonances in the energy region of E x = 19–27 MeV were found to be predominantly excited by ΔL = 1 transitions. The strength distribution of spin-dipole transitions with ΔS = 1 and ΔL = 1 were deduced. The obtained distribution was compared with a recent shell model calculation. Experimental results are reasonably explained by distorted-wave impulse-approximation calculations with the shell model wave functions. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Cross sections, analyzing powers and spin rotation parameters of proton elastic scattering from 58Ni and 120Sn have been measured at intermediate energies. Obtained data have been analyzed in the framework of relativistic impulse approximations. In order to explain the 58Ni data, it was necessary to modify NN interactions in the nuclear medium by changing coupling constants and masses of σ and ω mesons. For 120Sn, by assuming the same modification of NN interactions and by using proton densities deduced from charge densities, the neutron density distribution was searched so as to reproduce 120Sn data at 300 MeV. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

We study the renormalization group flow and infrared structure of higher dimensional GUTs. In higher dimensional theories the couplings approach much faster the infrared fixed points, compared to the four-dimensional case, due to their power law running behaviour. Therefore, tighter restrictions can be imposed to the couplings at the infrared region, enhancing thus the predictivity of the theories. We take a model with SU(5) as gauge group as a concrete example and show the running behaviour of the coupling constants. We also describe the predictions of low-energy parameters, e.g. masses of the top quark and superparticles that result from the fixed point structure of the RGEs. [ABSTRACT FROM AUTHOR]

The Laser-Electron-Photon facility at SPring-8 (LEPS) is now taking data for all hadronic reactions at compton-backscattered photon energies between 1.5 GeV and 2.4 GeV. A linearly polarized photon beam is incident on a liquid hydrogen target or nuclear targets. A large dipole spectrometer analyzes charged particles produced at forward angles. First results from SPring8/LEPS will be presented with special emphasis on the study of photoproduction of φ mesons near threshold. Some prospects for the near future will also be presented and discussed in close connection with photoproduction of hyperons. [ABSTRACT FROM AUTHOR]

Recent results from several researchers, in the area of automated high-order computation of quantities in QCD, the Standard Model, and other models are summarized. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Cross sections, analyzing powers and spin rotation parameters of proton elastic scattering from [sup 58]Ni and [sup 120]Sn have been measured at intermediate energies. By elastic scattering off N=Z nuclei like [sup 58]Ni at intermediate energies we can study medium modification of the nucleon-nucleon (NN) interaction inside the nucleus, because proton distributions in target nuclei are constrained by charge distributions measured by electron scattering and neutron distributions can be assumed to be the same as proton’s. In order to explain our experimental data of [sup 58]Ni at large scattering angles, it was found to be necessary to use experimental densities deduced from charge densities measured by electron scattering and to modify the coupling constants and the masses of exchanged σ and ω mesons in the RIA, assuming linear dependencies of meson properties to nuclear densities. Parameters of the medium effect have been searched to reproduce the data. For N≠Z nuclei, neutron density distribution can be extracted from the elastic scattering, assuming the same medium modifications fixed by the [sup 58]Ni data and using proton distributions obtained from charge distributions. We have searched neutron density distributions obtained from charge distributions. We have searched neutron density distribution so as to reproduce [sup 120]Sn data at the proton incident energy of 300 MeV. Deduced neutron distribution has an increase at the nuclear center, which is consistent with the 3s[sub 1/2] orbit wave function as expected in [sup 120]Sn. At energies other than 300 MeV, experimental data of [sup 120]Sn have been also well reproduced by the neutron distribution obtained at 300 MeV. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Polarization transfer (PT) coefficients in the [sup 12]C, [sup 28]Si(p,p') reactions at a scattering angle of 0° are measured at E[sub p] = 392 MeV. The strength of the isoscalar central spin-dependent part (V[sub σ]) of the effective nucleon-nucleon interaction is studied by using the sensitivity of the PT coefficients for the excitation of the 1[sup +], T=0 state in [sup 12]C to the V[sub σ] strength. It is found that distorted wave impulse approximation (DWIA) calculations employing the Francy and Love effective interaction well reproduce the measured PT coefficients. [ABSTRACT FROM AUTHOR]

Complete sets of observables in proton inelastic scattering from [sup 16]O have been measured at forward angles including 0°. Obtained spectra were decomposed into spin-flip and non spin-flip spectra by polarization transfer coefficients and spindipole strength spliting into several peaks was identified in the giant resonance region of E[sub x] = 19 ∼ 27 MeV in [sup 16]O. [ABSTRACT FROM AUTHOR]

We have constructed an experimental ensemble to measure polarization transfer observables in proton inelastic scattering at zero degrees. Excited states can simultaneously be measured for the excitation energy from 5 MeV to 35 MeV at E[sub p]=400 MeV. A fast data acquisition system has been developed to endure the large background event rate originated by the primary beam itself. We have found the effective analyzing power of the focal plane polarimeter slightly depends on the treatment of two-ray events. [ABSTRACT FROM AUTHOR]

With increasing of X-ray energy an interesting situation appears when due to different dependence of refraction and absorption on X-ray energy a sample becomes transparent but still produces refraction. So such samples become unvisible for usual absorption methods but could be analyzed with various phase contrast methodes. The situation becomes more actual for higher X-ray energy especially for range20-100keV. F. Polack and D. Joyeux described an extension of an interferential differential phase contrast to scanning X-ray microscopy. The principle is to illuminate two points of an object with coherent radiation and detect the fringe shift induced by small phase differences. Fresnel mirrors have been suggested to split a X-ray beam in two coherent ones. In this paper it is proposed instead to use bifocal (multi-focal) lenses. Design and fabrication process of the lenses are described. [ABSTRACT FROM AUTHOR]

X-rays refractive optics has made a real success in a hard radiation domain promising for many applications. An analysis made of refractive materials properties, which are most suitable for this new kind of X-ray focusing optics shows that in silicon refraction effects prevail on attenuation. A wide variety of technologies dedicated to microstructure formation on Si make it as most suitable one. Using electron beam lithography and deep plasma etching planar parabolic profiles are produced with the focal distance 1 m on 17.4 keV radiation. They are tested on synchrotron radiation at beamline X47 SRPING-8. Experiments carried out open the way to construct kinoform refracting profiles, which exceed simple parabolas in gain and aperture. A number of kinoform profiles on silicon is created for energies up to 50 keV, which at apertures 2mm have calculated gain up to 5000. Some focusing properties of such planar refracting profiles are discussed. [ABSTRACT FROM AUTHOR]

Focusing of 20 keV x-ray radiation using elliptical diffraction zones fabricated inside a silicon crystal have been observed successfully for the first time. These are the lenses with the first and third diffraction orders. An alignment of focusing elements was made with a 10 micron resolution x-ray imaging system. Focusing quality of the lenses have been investigated by using x-ray sensitive high resolution film and observing, under the light microscope, the shape of the registered focal spot first. And finally by scanning focal plane with pinhole and analysing three dimensional image. Experiments were made in a monochromatic beam. The signal/noise ratio of 300 have been obtained. These experiments open quite wide perspectives in focusing “hard” x-ray radiation up to 100 keV. Authors are hoping that this kind of focusing elements will find there real applications in microdiffraction experiments with energy about 20 kev and higher, in microfluorescence analysis experiments, near edge absorption experiments with micron spacial resolution. A new scheme to focus “hard” x-ray radiation have been suggested. Real geometry parameters for lens with elliptical diffraction zones was calculated for energy 60 keV. [ABSTRACT FROM AUTHOR]

We will measure the x-rays from kaonic 3He and 4He 3d→2p transition by using silicon drift detectors. Our precision goal is set to 1 eV to provide crucial information on the kaon-nucleus strong interaction in the low energy limit. The experiment is to be performed as one of the first experiment in the J-PARC hadron facility (J-PARC E17). An overview and the present status of the experiment are presented. [ABSTRACT FROM AUTHOR]

The 8Li(α,n)11B reaction has been measured directly and exclusively in the energy region of Ecm=0.45–1.75 MeV by using highly efficient detector system covering Ecm= 0.56 MeV, which corresponds to the Gamow window at T9=1. This experiment has been performed in the condition of inverse kinematics by using low-energy radioactive 8Li beam at the Tandem accelerator facility of Japan Atomic Energy Research Institute. The reaction cross section obtained in the present measurement is consistent with that of the previous exclusive measurements within the errors in an overlapping energy region, but is less than half of that of the inclusive measurements, in particular for lower energy region. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have successfully developed a technique to integrate an automatic event-generator generation system GRACE and a general-purpose event generator framework PYTHIA. The codes generated by GRACE are embedded in PYTHIA in the created event generator program. The embedded codes give information on parton-level hard interactions directly to PYTHIA. The choice of PDF is controlled by the ordinary parameter setting in PYTHIA. This technique enables us to create easy-to-handle event generators for any processes in hadron collisions. Especially, in virtue of large capability of GRACE, we can easily deal with those processes containing many (four or more) partons in the final state, such as multiple heavy particle productions. This project is being carried out as a collaboration between the Japanese Atlas group and the Minami-Tateya group, aiming at developing event generators for Tevatron and LHC experiments. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The segregation phenomena of binary granular mixtures in a horizontal rotating cylinder are investigated. For the sake of simplicity, the glass cylinder which is a half-filled with binary mixture of glass particles is adopted. The mixture consists of the same volumes of small size (diameter:0.2mm) and large size (diameter:0.6mm) glass particles. The rotation speed dependence of the long time scale segregation phenomena is studied. In a low rotation speed region, the initial narrow bands, which consist of small particles, gradually combined with each other and finally form one large band. On the other hand, in a high rotation speed region the initial narrow bands never combine with each other. The segregation phenomena in our case is thought to be caused by the drift motion of small particles along a inner axial core. We propose a new type model for numerical simulation which is able to take account of both effects of surface flow and inner drift of small particles. This model can reproduce the consecutive segregation phenomena obatained in our experiments. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]