The detecting module based on gallium arsenide detectors in digital mammography
Success in early breast cancer diagnostic depends on technical characteristics of detecting module. The most important is detector resolution. In this paper we represent quantum-sensitive detectors of X-rays based on GaAs for digital mammography systems. Electron/hole pairs created by radiation, which interact with the GaAs detectors, result current pulse at the detector output and specialist can see image immediately. Progress in development and investigation of a semiconductor material capable to provide reliable registration of single quanta of roentgen radiation. It is supposed to reduce patient radiation doze. At the same time, the system delivers high-quality images with resolution, contrast and clarity equal to film X-rays, or even better. Main advantages which can be achieved by using these detectors are analyzed.
THE DOSE AND IMAGE QUALITY IN MAMMOGRAPHY PRACTICE IN FINLAND
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ELECTROMAGNETIC DESIGN OF A RADIO FREQUENCY QUADRUPOLE FOR THE FRONT END TEST STAND AT RAL
The goal of the RAL front end test stand is to demonstrate cleanly chopped bunches of a 60mA H − ion beam at 3MeV. The acceleration of the H − ions from 65keV to 3MeV will be done using a radio frequency quadrupole (RFQ) operating at a resonant frequency of 324MHz. The two types of RFQ considered were a 4-vane and a 4-rod. The 4-vane has a higher Q-value but the post-production adjustment is limited. The 4-rod design is easier to manufacture but requires complicated cooling at 324MHz. The results of electromagnetic simulations using CST Microwave Studio are presented for the 4-vane type and 4-rod type RFQ.