Sealed ²²Na Sources for Positron Annihilation Lifetime Spectroscopy

Abstract:

Sealed radioactive sources of ²²Na for positron annihilation lifetime spectroscopy (PALS), free from the legal regulations, are commercially available from an American company. However, thick foils are used to seal ²²Na in these sources and large fractions of the positrons annihilate in the sealing materials. Further, it is pointed out that a long lifetime component over 1 ns appears in the positron lifetime spectrum acquired with the Kapton sealed source (POSK-22, IPL Inc.). In this research, attempts were made to develop high quality sealed positron sources, potentially free from regulations, for ubiquitous application of PALS. The sources prepared in the present work are of high quality and applicable to our new PALS, which does not require sample cutting and is potentially applicable to truly nondestructive, onsite inspection of various materials

• Periodical: Materials Science Forum (Volume 733)
• Pages: 310-313
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.733.310
• Online since: November 2012
• Authors: Masato Yamawaki, Yoshinori Kobayashi, Kenji Ito, Mikio Matsumoto, Hidetake Ishizu, Akiyo Umino, Kanehisa Hattori, Yoshihiro Watanabe
• Keywords: Anti-Coincidence, Positron Lifetime Spectroscopy, Scintillator, Sealed Na-22 Source

References

[1] K. Ito, Y. Kobayashi: RADIOISOTOPES 55(8), 469-472, (2006).

[2] M. Yamawaki, Y. Kobayashi, K. Hattori, Y. Watanabe: Japanese Journal of Applied Physics, 50 (2011) 086301.