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Nuclear resonant scattering quantum beats (QBs) spectrum reflects the interference information between all the possible energy transitions once which makes it difficult to analyze. Here we propose a new analysis method that can give the hyperfine structure directly from the QBs. As a case study, we analyzed QBs of a hematite sample at several temperature points across its Morin temperature. We observed that the transverse between the excited energy transitions which is accordance with the results obtained by the conventional MS method. [ABSTRACT FROM AUTHOR]

A wavefront analysis indicates that a flexural wave propagates at a helix angle with respect to the pipe axis. The expression for calculation of the helix angle for each flexural mode is given, and the helix angle dispersion curves for flexural modes are calculated. According to the new understanding of flexural guided waves, a magnetostrictive helical array transducer (MHAT) is proposed for selectively exciting a single predominant flexural torsional guided wave in a pipe and inspecting spiral welded pipes using flexural waves. A MHAT contains a pre-magnetized magnetostrictive patch that is helically coupled with the outer surface of a pipe, and an array of novel compound comb coils that are wrapped around the helical magnetostrictive patch. The proposed wideband MHAT possesses the direction control ability. A verification experiment indicates that flexural torsional mode T(3,1) at center frequency f=64kHz is effectively actuated by a MHAT with 13-degree helix angle. A 20-degree MHAT is adopted to inspect a spiral welded pipe, an artificial notch with cross section loss CSL=2.7% is effectively detected by using flexural waves. [ABSTRACT FROM AUTHOR]

A wavefront analysis indicates that a flexural wave propagates at a helix angle with respect to the pipe axis. The expression for calculation of the helix angle for each flexural mode is given, and the helix angle dispersion curves for flexural modes are calculated. According to the new understanding of flexural guided waves, a magnetostrictive helical array transducer (MHAT) is proposed for selectively exciting a single predominant flexural torsional guided wave in a pipe and inspecting spiral welded pipes using flexural waves. A MHAT contains a pre-magnetized magnetostrictive patch that is helically coupled with the outer surface of a pipe, and an array of novel compound comb coils that are wrapped around the helical magnetostrictive patch. The proposed wideband MHAT possesses the direction control ability. A verification experiment indicates that flexural torsional mode T(3,1) at center frequency f=64kHz is effectively actuated by a MHAT with 13-degree helix angle. A 20-degree MHAT is adopted to inspect a spiral welded pipe, an artificial notch with cross section loss CSL=2.7% is effectively detected by using flexural waves. [ABSTRACT FROM AUTHOR]

Millions of miles of pipes are being used in both civil and industrial fields. Spiral-welded pipes, which are widely applied in fields such as drainage, architecture as well as oil and gas storage and transportation, are difficult to inspect due to their complex geometry. Guided waves have shown a great potential in Non-Destructive Evaluation (NDE) and Structural Health Monitoring (SHM) for such cases. Flexural guided waves that propagate at a helix angle relative to the axial direction of pipe, are the most appropriate modes for inspecting spiral-welded pipes. The classical Normal Mode Expansion method (NME) is adopted to disseminate the forced response and perturbation analysis of a steel pipe with respect to a time delay circular loading. A time delay circular array transducer (TDCAT) is proposed for the purpose of exciting pure flexural mode in pipes. Pure flexural mode can be excited when the time delay parameter is specifically designed. The theoretical prediction is verified by finite element numerical evaluation and spiral-welded pipe inspection experiment. [ABSTRACT FROM AUTHOR]

For determination of the Avogadro’s number, a self-referenced lattice comparator established at the Photon Factory to deal with a d-spacing mapping measurement over the cross section of a 4 ∼ 5 inches FZ silicon rod. For uncertainty of 1×10-8 of the unit cell volume, it is necessary to measure lattice parameter of silicon with resolution of 3×10-9 at least. In this paper, we report the principle of our lattice comparator, characterize our measurement system, and show some mapping measurement results of FZ silicon with resolution of 3×10-9. [ABSTRACT FROM AUTHOR]

Various kinds of high-resolution monochromators which have the energy resolution (ΔE/E) of ∼ 10-7 in X-rays region, have been developed at Nuclear Resonant Scattering Beamline BL09XU, SPring-8. They were designed at the nuclear transition energies of 181Ta (6.2 keV), 57Fe (14.4 keV), 151Eu (21.5 keV), 149Sm (22.5 keV), 40K (29.8 keV) and 121Sb (37.1 keV). All of these developed monochromators worked well and have been utilized for user experiments of nuclear resonant scattering. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have developed a fast and stable measuring system of lattice spacing with precision of 10-8 for a silicon crystal at the Photon Factory. Using a combination of this system with an autocollimator, we can not only measure d-spacing, but also can determine lattice plane orientation with sub-arcsec resolution in the same measurement process. We report a mapping measurement of a Boron-doped CZ silicon wafer with 1mm2 spatial resolution. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

Backscattering of α-quartz (0 6 10) was investigated using 14.4 keV 57Fe Mössbauer photons from α-57Fe2O3 at nuclear resonant scattering beamline BL09XU, SPring-8. The α-quartz crystal was heated to around 353 K by an oven so that the Bragg angle of α-quartz 0 6 10 diffraction meats 90 degrees. Energy width of the reflection was measured by changing temperature of the oven. The measured bandwidth is 1.14(33) meV. Backscattering by a α-quartz crystal can be applied for high-energy-resolution monochromator or analyzer. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

We report improvement of the Self-referenced lattice comparator using a wide brush beam with size of 16 mm × 0.3 mm and a pair of one-dimensional position sensitive X-ray counters instead of using a pencil beam with size of 1 mm × 0.3 mm and a pair of PIN photodiode detector in the former system. The experimental time is accelerated by a factor of more than ten times. Since we use a brush beam for the measurement, the wavelength alone the horizontal beam width positions are different, it is necessary to establish a data correction procedure for the lattice comparator. We reported our first data after the system improved, the spatial resolution of mapping measurement reached to 0.5 mm × 0.3 mm, that is higher than the previous system. [ABSTRACT FROM AUTHOR]