Detector for positron annihilation life spectrometer

Abstract

This invention relates to one positron annihilation life spectrum detector, which comprises initial detector and terminal detector and is different to the regular detector by adopting the different terminal channel detector to the initial channel and locating one round well in the center of the flash of the terminal detector and putting specimen and 22Na positron emission power.

Description

technical field [0001] The invention relates to a positron annihilation lifetime spectrometer (Positron Annihilation Lifetime Spectrometer), in particular to a detector of the positron annihilation lifetime spectrometer. Background technique [0002] Positrons are the antiparticles of electrons. When positrons and electrons meet, annihilation occurs, and the entire mass is converted into two gamma photons with energy of 0.511MeV and opposite directions; the annihilation lifetime of positrons is inversely proportional to the electron concentration in the material , in metals and alloys with complete lattices, the annihilation lifetime of positrons is in the range of 100-250 ps, ​​and in the defect of materials, the annihilation lifetime of positrons is in the range of 200-500 ps, ​​which is called the capture annihilation of positrons, and the annihilation of positrons The lifetime becomes longer as the size of the defect increases. Different types of defects have different p...

AI Technical Summary

Problems solved by technology

That is, E γ1 and E γ2 1.28MeV and 0.511MeV respectively, the energy of the two 0.511MeV gamma rays generated during the annihilation of the positron, one of the energy of the 0.511MeV gamma ray is lost in vain, so E γ2 The smaller the value, the larger the FWHM value, and the poorer the time resolution of the spectrometer

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