Measurement of Orthopositronium Decay Rate Using SiO2 Powder: Integration of Thermalization into Time Spectrum Fitting Procedure
نویسندگان
چکیده
The intrinsic decay rate of orthopositronium (o-Ps) formed in SiO2 powder was measured using a modified method which determined the time dependence of the pick-off annihilation rate using high-energyresolution germanium detectors. That is, the main systematic error due to thermalization was accounted for and integrated into the time spectrum fitting procedure. The averaged value was found to be λo-Ps = 7.0399 +0.0020 −0.0021 (stat.) ± 0.0015(sys.)μs, which agrees well with the O(α) QED prediction; varying 2.8-4.2 experimental standard deviations from other measurements.
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