Improved Measurement of γ-Energy from Parapositronium 2γ-Decay

Peng Liangqiang; Zhang Tianbao; Wang Haidong; Meng Bonian; Yin Guoli

Chinese Physics C> 1995, Vol. 19> Issue(11) : 987-990

Improved Measurement of γ-Energy from Parapositronium 2γ-Decay

Application Division,Institute of High Energy Physics,The Chinese Academy of Sciences,Beijing 1000801 EG&G Ortec INC.,Beijing Office

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Abstract：
Using a silica aerogel sample with oxygen gas filled as the positronium(Ps)source and a time selecting energy spectrometer,the measurement of the y-energy of parapositronium(p-Ps)2y-decay is further improved and the result of hv=510995. 34±0.69eV is obtained by a slithering comparison with the precisely known y-energies of ¹⁹²Ir.The rest mass of a pair of positron and electron is determined by the correction with the binding energy of Ps,which shows a mass equality within 1.4ppm between positron and electron by the comparison with the rest mass of electron.

References

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E.R.Cohen,B.N.Taylor,Rev.Modern.iPhys/i,59（1987）1121.[2] R.Lewis,Elementary Particles and Symmetries,Gardon and Breach（1975）.[3] 张天保、王海东、沈智奇，高能物理与核物理，15（1991）486.[4] 张天保等，中国科学，A9（1992）970.[5] 张天保、徐敏，高能物理与核物理，14（1990）289.[6] T.B.Chang et al,iNucl/i.Instr.Methode,A325（1993）196.[7] 张天保，物理，4（1990）228.[8] R.D.Deslatts et al,Ann.iPhys/i,129（1980）378.

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Peng Liangqiang, Zhang Tianbao, Wang Haidong, Meng Bonian and Yin Guoli. Improved Measurement of γ-Energy from Parapositronium 2γ-Decay[J]. Chinese Physics C, 1995, 19(11): 987-990.

Peng Liangqiang, Zhang Tianbao, Wang Haidong, Meng Bonian and Yin Guoli. Improved Measurement of γ-Energy from Parapositronium 2γ-Decay[J]. Chinese Physics C, 1995, 19(11): 987-990. shu

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Received: 1900-01-01
Revised: 1900-01-01

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沈阳化工大学材料科学与工程学院沈阳 110142

Improved Measurement of γ-Energy from Parapositronium 2γ-Decay

Corresponding author: Peng Liangqiang,

Application Division,Institute of High Energy Physics,The Chinese Academy of Sciences,Beijing 1000801 EG&G Ortec INC.,Beijing Office

Received Date: 1900-01-01
Accepted Date: 1900-01-01
Available Online: 1995-11-15

Abstract: Using a silica aerogel sample with oxygen gas filled as the positronium(Ps)source and a time selecting energy spectrometer,the measurement of the y-energy of parapositronium(p-Ps)2y-decay is further improved and the result of hv=510995. 34±0.69eV is obtained by a slithering comparison with the precisely known y-energies of ¹⁹²Ir.The rest mass of a pair of positron and electron is determined by the correction with the binding energy of Ps,which shows a mass equality within 1.4ppm between positron and electron by the comparison with the rest mass of electron.