RESUMEN
To monitor the position and profile of therapeutic carbon beams in real-time, in this paper, we proposed a system called HiBeam-T. The HiBeam-T is a time projection chamber (TPC) with forty Topmetal-II- CMOS pixel sensors as its readout. Each Topmetal-II- has 72 × 72 pixels with the size of 83 µm × 83 µm. The detector consists of the charge drift region and the charge collection area. The readout electronics comprise three Readout Control Modules and one Clock Synchronization Module. This Hibeam-T has a sensitive area of 20 × 20 cm and can acquire the center of the incident beams. The test with a continuous 80.55 MeV/u 12C6+ beam shows that the measurement resolution to the beam center could reach 6.45 µm for unsaturated beam projections.
RESUMEN
Single-ion monitoring is a key requirement for many energetic heavy-ion experiments, e.g., the laboratory simulation of the single event effect of semiconductor devices under heavy ion bombardments. We have developed a two-dimensional position-sensitive and timing monitor of individual ions. It is composed of a thin aluminum foil, a pair of microchannel plate detectors, and electrostatic and magnetic fields. When energetic heavy ions pass through the aluminum foil, secondary electrons generated on each side of the foil are guided by the fields to the corresponding detector. Both the hitting position and the arrival time of the secondary electrons on corresponding detectors are measured in coincidence. A test with an 241Am α source shows that the present monitor is capable of discriminating true events from heavy background radiations. A position resolution of 1.0 mm and a recording time resolution of 50 ns have been realized in the test.
RESUMEN
A two-dimensional position-sensitive microchannel plate detector, with a Ø100 mm sensitive area and equipped with four integrated amplifiers, is realized with a new anode scheme. The anode is constructed by two independent one-dimensional resistive anodes, each consisting of an array of parallel copper strips connected by resistors in series on a printed circuit board (PCB). The arrays are perpendicularly aligned to realize two-dimensional position resolution, with the intervals between the adjacent strips on the PCB nearer to the microchannel plate cut out to allow electrons passing through. The detector is tested with an 55Fe x-ray source, and a position resolution of 0.38 mm is achieved.
RESUMEN
Based on the charge-division method, a compact detector system for charged particles is constructed. The system consists of a pair of micro-channel plates, a novel two-dimensional position-sensitive cross-connected-pixels resistive anode, and specially designed front-end electronics that can directly drive analog-to-digital converters. The detector is tested with an 241Am α-source. A position resolution of better than 0.3 mm and a maximum distortion within 0.5 mm in the active dimensions of 100 mm diameter are achieved.