Micron-sized diamond anvils with a 3 μm culet were successfully processed using a focused ion beam (FIB) system and the generation of high pressures was confirmed using the double stage diamond anvil cell technique. The difficulty of aligning two second-stage micro-anvils was solved via the paired micro-anvil method. Micro-manufacturing using a FIB system enables us to control anvil shape, process any materials, including nano-polycrystalline diamond and single crystal diamond, and assemble the sample exactly in a very small space between the second-stage anvils. This method is highly reproducible. High pressures over 300 GPa were achieved, and the pressure distribution around the micro-anvil culet was evaluated by using a well-focused synchrotron micro-X-ray beam.
Abstract We have observed the late Class I protostellar source Elias 29 at a spatial resolution of 70 au with the Atacama Large Millimeter/submillimeter Array as part of the FAUST Large Program. We focus on the line emission of SO, while that of 34 SO, C 18 O, CS, SiO, H 13 CO + , and DCO + are used supplementarily. The spatial distribution of the SO rotational temperature ( T rot (SO)) is evaluated by using the intensity ratio of its two rotational excitation lines. Besides in the vicinity of the protostar, two hot spots are found at a distance of 500 au from the protostar; T rot (SO) locally rises to 53 −15+25 K at the interaction point of the outflow and the southern ridge, and 72 −29+66 K within the southeastern outflow probably due to a jet-driven bow shock. However, the SiO emission is not detected at these hot spots. It is likely that active gas accretion through the disk-like structure and onto the protostar still continues even at this evolved protostellar stage, at least sporadically, considering the outflow/jet activities and the possible infall motion previously reported. Interestingly, T rot (SO) is as high as 20–30 K even within the quiescent part of the southern ridge apart from the protostar by 500–1000 au without clear kinematic indication of current outflow/jet interactions. Such a warm condition is also supported by the low deuterium fractionation ratio of HCO + estimated by using the H 13 CO + and DCO + lines. The B-type star HD147889 ∼0.5 pc away from Elias 29, previously suggested as a heating source for this region, is likely responsible for the warm condition of Elias 29.
The monochromatic X-ray source based on parametric X-ray radiation (PXR) was developed by using Si(111) perfect crystals and the electron beam from the 125-MeV linac at Nihon University. Since the X-ray beam from the PXR system has a large exposure area with uniform flux density, the PXR-based source is suited for X-ray radiography. In addition to ordinary radiography, X-ray absorption spectroscopy and phase-contrast imaging have been developed as advanced applications of PXR. The absorption spectra of several samples were obtained using the energy dispersion of PXR, and the X-ray absorption fine structures (XAFS) were actually found in the spectra. With respect to phase-contrast imaging, refraction-contrast images have been obtained by using the X-ray diffraction in the (+, −, +) arrangement of perfect crystals. The high-contrast and the phase-reversal of the images taken in the experiment suggest that LEBRA-PXR has a high spatial coherence sufficient for phase-contrast imaging.
A cryogenic C-band photocathode RF-gun operating at 20 K is under development at LEBRA in Nihon University. The RF-gun is of the BNL-type 2.6-cell pillbox cavity with the resonant frequency of 5712 MHz. The 6N8 high purity OFHC copper (corresponding to RRR-3000) is used as the cavity material. From the theoretical evaluation of the anomalous skin effect, the quality factor Q of the cavity at the operating temperature of 20 K has been expected to be approximately 60000. The cavity basic design and the beam bunching simulation were carried out using Poisson Superfish and General Particle Tracer (GPT). Machining and diffusion bonding of the RF-gun cavity was carried out in KEK. After diffusion bonding the Q0 value of the -mode resonance at the room temperature (23.5 °C) was approximately 11440.
X-ray imaging based on small-angle X-ray scattering (SAXS) was carried out using the parametric X-ray radiation (PXR) source at the Laboratory for Electron Beam Research and Application (LEBRA) of Nihon University. The experimental setup employed in this novel imaging approach is the same as that employed in diffraction-enhanced imaging (DEI), a kind of X-ray phase-contrast imaging method. In SAXS-based imaging, the image contrast is correlated with the broadening of the rocking curve peak due to the scattering from micron- or sub-micron-sized grains in the sample material. An experiment using the 25.5-keV PXR beam demonstrated that SAXS-based imaging with PXR provides a substantially strong contrast for granular materials despite the extremely low density of the material.
We study a combination of velocity bunchings and the coherent undulator radiation at THz region by simulation. The combination of velocity bunchings brings some freedom in energy choice while keeping the bunch length shorter efficiently. Hence the coherent condition can be met for THz radiation at undulator allowing some range of radiation wavelength.
A compact system for generating extreme pressures and temperatures was developed for versatile experiments based on laser-heated diamond anvil cell technique. This system has been used for inelastic X-ray scattering measurements for iron.
Recent spectroscopic observations by sensitive radio telescopes require accurate molecular spectral line frequencies to identify molecular species in a forest of lines detected. To measure rest frequencies of molecular spectral lines in the laboratory, an emission-type millimeter and submillimeter-wave spectrometer utilizing state-of-the-art radio-astronomical technologies is developed. The spectrometer is equipped with a 200 cm glass cylinder cell, a two sideband (2SB) Superconductor-Insulator-Superconductor (SIS) receiver in the 230 GHz band, and wide-band auto-correlation digital spectrometers. By using the four 2.5 GHz digital spectrometers, a total instantaneous bandwidth of the 2SB SIS receiver of 8 GHz can be covered with a frequency resolution of 88.5 kHz. Spectroscopic measurements of CH$_3$CN and HDO are carried out in the 230 GHz band so as to examine frequency accuracy, stability, sensitivity, as well as intensity calibration accuracy of our system. As for the result of CH$_3$CN, we confirm that the frequency accuracy for lines detected with sufficient signal to noise ratio is better than 1 kHz, when the high resolution spectrometer having a channel resolution of 17.7 kHz is used. In addition, we demonstrate the capability of this system by spectral scan measurement of CH$_3$OH from 216 GHz to 264 GHz. We assign 242 transitions of CH$_3$OH, 51 transitions of $^{13}$CH$_3$OH, and 21 unidentified emission lines for 295 detected lines. Consequently, our spectrometer demonstrates sufficient sensitivity, spectral resolution, and frequency accuracy for in-situ experimental-based rest frequency measurements of spectral lines on various molecular species.
Light and electron microscopic studies and energy dispersive X-ray analysis disclosed that the essential cause of gingival discoloration following the placement of a metallic crown, was marked deposition of melanin pigment. Deposition of melanin pigment was observed in epithelial cells, on basement membranes, and in fibroblasts, macrophages and among intercellular ground substance of the proprial layer. Brown or dark brown colored granules were observed in the deep portion of the proprial layer. Some metallic elements as silver and sulfur were detected. It was presumed that these materials were dental metals accidentally implanted in gingival tissues during the therapeutic procedure. The deposition of melanin pigment closely corresponded with mucosal tissue where these materials were present in the deep portion of the proprial layer. These findings suggested that these materials influenced the physiological metabolism of melanin and induced its pathological deposition in the proprial tissue.
An automatical measuring method of distributions and mean diameters of atomized droplets is developed by means of using electronic circuits and digital computer. The scheme of the method is as follows. A photograph of particles mounted on the rotating drum is scanned by a light spot. The black or white light pulses generated from scanning apparatus are converted through electronic circuits into digital signals, and are punched on a tape by means of punching machine.The distributions and mean diameters are computed by digital computer according to the developed logical programs. The ring shaped shadows which are characteristic of the transparent liquid droplets and osculated shadows of particles were descriminated clearly by using the proposed programs, which were impossible for automatic counters hitherto. The similar device is applicable for the measurements of various powders or the analysis of many sorts of diagrams.
