[en] The ratios of the double to single ionization cross sections of helium impacted by partially stripped C^q+ ions (q = 1,2,3,4) in energy range of 1.5-7.5 MeV were measured by using the time of flight procedure. The n-body classical trajectory Monte Carlo calculation was carried out to get the Olson-Schlachter scaling. The single and double ionization cross sections of helium were obtained by comparing the cross section ratios of the present work with the Olson-Schlachter scaling

[en] We are currently investigating the spatial resolution of highly pixelated Cadmium Zinc Telluride (CZT) detector for imaging application. A 20 mm × 20 mm × 5 mm CZT substrate was fabricated with 600 μm pitch pixels (500 μm anode pixels with 100 μm gap) and coplanar cathode. Charge sharing between two pixels was studied using collimated a 122 keV gamma ray source. Experiments show a resolution of 125 μm FWHM for double-pixel charge sharing events when the 600 μm pixelated and 5 mm thick CZT detector biased at -1000 V. In addition, we analyzed the energy response of the 600 μm pitch pixelated CZT detector. (authors)

[en] A simple model for the direct ionization and transfer ionization probabilities in A²⁺ + He collisions in a wide projectile energy range is proposed based on the Bohr-Lindhard model and the classical statistical model. The calculated cross sections are in satisfactory agreement with the experimental data available. (authors)

[en] The dependence of the ratio R₁ for transfer ionization to single capture for C^q+, N^q+, O^q+, Ne^q+ ions on Ne target upon the electronic structure of the projectile is studied by using position sensitive and time-of-flight techniques. It is found that for A^q+-Ne collisions the ratio R₁ decreases as the atomic number of the projectile increases for q=4,5,6,7 sequences which differs markedly from the results we obtained for A^q+-Ar collisions. The difference is explained by using a statistical model and the orbital penetration picture. Comparison of the R₁ ratios of A⁴⁺-Ne and A⁴⁺-Ar collisions provides strong evidence for the increase of the binding energy of the target valence electron after single electron capture. The increase in binding energy depends both upon the atomic number of the projectile Z₁ and the target atom Z₂. The larger Z₁, the larger the increase in binding energy, while the larger Z₂, the smaller the increase in binding energy

[en] We investigate angular distributions of the transmitted 60 keV and 120 keV O³⁺ ions through nanocapillaries with 50 nm diameter and 10μm length. The experimental results are in agreement with the 'guiding effect' found by Stolterfoht et al. For different tilted angles of the nanocapillary membrane with respect to the beam, the angular distributions of the transmitted ions are measured by a one-dimensional micro-channel plate (MCP) detector. Moreover, the dependence of this guiding effect on the projectile energy is studied. (authors)

[en] The thin target M-shell X-ray production cross sections have been measured for Ta, Au and Bi with impact over the energy from 0.6 to 2.75 MeV. The measured cross sections are compared with the plane wave Born approximation (PWBA) theory

[en] Aiming at the aging test requirements of the vacuum components, a HV pulse generation system based on the PLC control is designed. It consist of industry PLC and industry computer, digital controls are implemented to the direct current charge supply, time control to the hydrogen thyratron, and switch control to polarity conversion relay and current limiter. Using the digital oscilloscope, it acquires the HV pulse waveform information of voltage, current and time. It has the nice interface of human-computer interaction based on the WINCC V6.2 Software. It can judge and test the breakdown of the vacuum components, and run the different aging processes in automatic condition. Because of using PLC, the system can work stably, dependably and for a long-term at the severe circumstances. (authors)

[en] High T_c superconducting Y-Ba-Cu-O sample is bombarded by 20 keV Ar⁺ ion beam. The composition of the bulk sample before and after sputtering is analyzed by means of PIXE method. The composition change at the surface of the bulk sample after sputtering is presented and discussed. The particles sputtered from the surface of the bulk sample are collected on a substrate of silicon. The composition of the film formed on the substrate is determined by PIXE (Proton induced X-ray emission) and RBS (Rutherford Backscattering Spectroscopy) combined with ¹⁶O(α, α)¹⁶O nuclear resonance scattering

[en] This article reviews the research and development status of γ detector crystals in PET system. We investigated the γ-ray detection efficiency, light yield, spectrum, light decay time constant, energy resolution and other properties of NaI (Tl), BGO, LSO/LYSO and CZT detectors. The performance of clinical PET system and pre-clinical PET system were affected by the crystal material including overall size, position resolution, scattering fraction, and sensitivity. We also compared the performance of domestic and foreign PET systems made by BGO and LSO/LYSO detectors. This research would guide the development and application of PET system design. (authors)

[en] A wireless monitoring system applied in the radioactive source storage vault is designed in this paper, based on the environmental radiation dose monitoring and General Packet Radio Service (GPRS) techniques. It introduced hardware and software design of the system. The system adopted monitor terminal to collect and process field data, and then the environmental radiation dose information will be uploaded to a specific monitoring platform through the GPRS network. As a result, the safety of the radioactive source storage vault is guaranteed. (authors)