RESUMO
A module of a wireless high voltage generator was tested immersed in both gaseous and liquid environments providing electrical insulation. The overall performance of the module as well as a detailed performance of the key components are reported, and a comparison between the results in gas and liquid is given. The tests performed on the liquid dielectric show that it is a valid alternative to high pressure gas electrical insulation.
RESUMO
A multi-element tissue-equivalent proportional counter (TEPC), based on a single gas electron multiplier (GEM) foil of standard geometry, has been constructed with 16 cylindrical sensitives volumes. In this article, the design of this novel counter is described and first microdosimetric measurements are presented. To study the response of the GEM-TEPC to both low and high linear energy transfer radiation fields, the microdosimetric spectra due to a 137Cs gamma-ray source and to fast neutrons from 7Li(d,n)8Be reaction have been measured using pure propane gas at low pressure, in order to simulate a tissue site of about 1 µm equivalent size. The comparison with spectra measured with a spherical TEPC and with a mini-TEPC demonstrates promising properties for application of the GEM-TEPC for microdosimetric applications.