JJAP Conference Proceedings

JJAP Conf. Proc. 2, 011002 (2014) doi:10.7567/JJAPCP.2.011002

Effect of constraining the source lifetime parameter during least-square-fit analysis on positron lifetime measurements

Masato Yamawaki1, Kenji Ito1, Yoshinori Kobayashi1, Kanehisa Hattori2, Yoshihiro Watanabe2

  1. 1National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki 305-8565, Japan
  2. 2TOYO SEIKO Co., Ltd, Yatomi, Aichi 490-1412, Japan
  • Received May 30, 2014
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We examined the effect of constraining the positron source lifetime parameter during a least-square fitting (LSF) of positron annihilation lifetime (PAL) data on the resultant lifetimes, as determined from the fit result. The effect was assessed using calculated PAL spectra and also experimentallyobtained spectra for single-crystal silicon with different measurement statistics, in order to discuss the uncertainty of the resultant lifetime for a sample having a relatively short lifetime of around 220 ps. The obtained results suggest that constraining the positron source lifetime during the LSF analysis results in a relatively minor uncertainty of the sample lifetime in comparison with that due to the measurement statistics.

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