Lifetime of Positrons in Matter

Yi Gao

《International Core Journal of Engineering》 10卷1期 (2024/01) Pp. 274-283

https://doi.org/10.6919/ICJE.202401_10(1).0039

摘要

Studying positrons in various materials provides valuable information about the fundamental interactions of particles and the properties of matter. For example, medical imaging technique plays critical roles in modern healthcare domain. However, the positron annihilation is the principle behind positron emission tomography (PET). Research on positron lifetimes and annihilation characteristics helps improve the accuracy and resolution of PET scans, contributing to advancements in medical imaging and diagnostics. In this experiment, the source of positron is from Isotope ^(22)Na. Comparing to other general source of positron source such as ^(18)F and ^(11)C, ^(22)Na has three advantages: High Availability, High Positron Yield and Gamma-ray Emission.

關鍵字

Lifetime of Positrons ； PET ； Parapositronium ； Orthopositronium ； ^(22)Na-source ； ^(22)Na-spectrum ； ^(60)Co-spectrum

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