A radio interferometer capable of azimuth-elevation direction finding for geosynchronous satellites has been developed. The interferometer has two small-diameter antennas and four movable planar ...mirrors. The movable mirrors reflect the microwaves from the satellite and guide them to the fixed receiving antennas. Two of the movable mirrors are mounted on a rotary arm, so that the baseline of the interferometer can rotate in the horizontal plane. This configuration enables the interferometer to eliminate phase-ambiguity problems and cable-phase errors, resulting in a direction finding accuracy of better than 0.01 deg in the Ku band.
Many people are anxious about radiation exposure for the reason that radiation cannot be seen. With the aim of devising a way for medical personnel to perform their medical duties without worry about ...radiation exposure, we attempted safety management using a system that displays the air dose of radiation in real time. Measurements were made in a lung ventilation scintigraphy examination room with the use of Xe-133. An SCI-type RI detector from Hamamatsu Photonics, which displays the air dose rate in real time, was used for the measurements. These radiation measurements were continued from the start to finish of the examination. The measurements were made in two locations, on the patient inhalation tube side and on the opposite side. Measurements were made on the patient tube side in 24 tests and on the opposite side in 12 tests. The maximum air dose rate was 3.7 ± 2.1 μSv/h on the patient tube side and 1.1 ± 0.5 μSv/h on the opposite side. Thus, the level on the opposite side was about 1/5 that of the tube side. To accurately perform lung ventilation scintigraphy, a medical worker needs to observe the patient's breathing status up close. Because of this, some medical workers are worried about radiation exposure during tests. The simplest way to reduce exposure would be to maintain a distance from the examination tube that is the source of radiation. The measurements in this study were made to encourage medical workers' recognition of this fact. Displaying specific numbers not only serves as basic data for managing staff operations, but is also thought to reassure workers through visualization.
Human alveolar echinococcosis (AE) is caused by the accidental ingestion of Echinococcus multilocularis eggs. Early detection is essential as surgical resection is the only treatment for a complete ...cure. However, details are unclear about changes in the antibody response during the initial stages of infection, yet such information is useful for early serodiagnosis. Therefore, a long-term investigation was performed into the time course of the antibody response before 'positive' detection. Patient sera were used for enzyme-linked immunosorbent assay (ELISA) and Western blotting (WB) analysis using crude antigens extracted from E. multilocularis protoscoleces. Rats were experimentally infected with AE and similarly analysed by ELISA and WB. Among the markers for diagnoses, the 18 kDa band (main marker) appeared last in the preoperative stages and disappeared first after operation in a WB test. Although the 18 kDa antigen can be useful as a marker for AE diagnosis, it cannot contribute to the detection of some patients before the 18 kDa band appearance. To avoid misdiagnosis, different diagnostic antigens such as the 26-28 and 7-8 kDa bands should also be considered. These bands tend to appear earlier than the 18 kDa band and thus offer the potential for early detection of AE. We first observed changes in the antibody response in a relatively early stage after infection in human AE cases. Notably, changes in the antibody response of two intermediate species were similar. These findings provide valuable information for the early detection of human AE cases in the future.
Performance of the OEDO beamline Hwang, J W; Michimasa, S; Yamada, K ...
Journal of physics. Conference series,
12/2020, Volume:
1643, Issue:
1
Journal Article
Peer reviewed
Open access
The OEDO (Optimized Energy Degrading Optics for RI beam) beamline has been developed to obtain low-energy (10 - 50 MeV/u) RI beams by slowing down the secondary beams at RIBF, RIKEN. Such beams are ...useful probes to investigate nuclear structure by means of nucleon transfer and Coulomb excitation reactions. The beamline is designed to produce a well-focused beam of small energy spread with the help of the angle-tuneable wedge degrader and the radio-frequency deflector. The commissioning and first physics experiments using the OEDO beamline were carried out in 2017. OEDO successfully provided the energy-degraded beams of Se, Zr, and Pd. Its performance including the optics and transmission was evaluated using those experimental data and it functions properly as designed. We expect that our novel beamline shed a light on the experimental approaches involving nuclear reactions at several tens of MeV/u to expand our knowledge of nuclei far beyond the line of stability.
•Multi-wire drift chambers were developed for high intensity beams of 1MHz.•Low-pressure gas is used to minimize the effect of multiple scattering.•Tracking efficiencies reached almost 90% for Z from ...2 to 7.•Position resolution of 300μm was achieved for beams of 1MHz.
Low-pressure multi-wire drift chambers have been developed to track high-intensity radioactive isotope beams at the energies of around 200MeV/nucleon. In order to minimize the effect of multiple scattering by radioactive isotope beam, the thickness of the detectors were minimized by using isobutane gas at low pressure (10kPa). The performance of the position resolution, the tracking efficiency, and the beam intensity capability were evaluated as a function of atomic number and applied voltage. As a result, an overall position resolution of 300 μm was achieved for radioactive isotope beams with an intensity of 1MHz. The details of the design specifications and performances of the low-pressure multi-wire drift chambers are described.
•Report on recent achievement of the SHARAQ spectrometer.•Demonstration of two ion optics modes for high-resolution spectroscopy.•Discussion on measured transport matrix elements by comparison with ...designed values.•Demonstration of event-by-event momentum tagging by the achromatic transport.•Achievement of momentum resolution of 1/8100 by the dispersion-matching transport.
The SHARAQ spectrometer and High-Resolution Beamline, which began operation in March 2009, have been put into use for six experiments using charge exchange reactions with radioactive isotope beams. For experiments at SHARAQ, detector developments and ion optics studies continue to improve performance in high-resolution nuclear spectroscopy. We have introduced improved timing resolution with CVD diamond detectors, high count-rate beamline tracking detectors and development of multi-particle detection by cathode-readout drift chambers. Ion-optics studies for the high-resolution achromatic (HA) and dispersion-matching (DM) transport modes are also reported here. Momentum tagging in the HA mode demonstrated an improvement in spectroscopic resolution with respect to the momentum spread of the radioactive beam. For the DM transportation mode, a momentum resolution of 1/8100 (FWHM) was achieved by taking into account the positions and angles of the beam at the third focal plane of BigRIPS.
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