α-particle spectrometer based on xenon gas ionization chamber using coplanar electrodes

摘要

A parallel plate gas ionization chamber with coplanar electrodes was designed and developed to be used as an alpha-particle spectrometer measuring low level alpha-emission rates in environmental samples from the vicinity of nuclear power plants. The chamber was filled with a 3 atm gas mixture of Xe + 0.7% CH4. Its performance was investigated using a mixed alpha-particle source (Np-237, Am-241, and Cm-244). An excellent energy resolution of 59 keV (1.0%) in fwhm for 5.81 MeV 244 Cm a-particles was obtained, which is enough to identify major sources of alpha radioisotopes (U-238,U-235,Np-237,(239)pu,(238)pu,Am-241,Cm-244) to be found near nuclear power plants.