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arXiv · 2205.08739

NaI(Tl) crystal scintillator encapsulated in two organic-scintillator layers with pulse shape data analysis

Jinyoung Kim·Yujin Lee·Byoung-cheol Koh·Chang Hyon Ha·Byung Ju Park·In Soo Lee·Hyun Su Lee
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Abstract

Thallium-doped sodium iodide (NaI(Tl)) crystals are widely used in radiation detection applications, from gamma-ray spectroscopy to particle dark matter searches. However, if the crystal is exposed to relative humidity of even a few percent, its light emission degrades, making the crystal impractical as a detector. Surrounding the crystal with organic scintillators not only protects the surface of the crystal from humid air but also offers a new capability to tag backgrounds such as external gamma rays and surface contaminations. We developed a detector that is constructed by fully encasing a NaI(Tl) crystal in a plastic scintillator and then immersing the plastic-crystal assembly in liquid scintillator. Using data collected from this triple phoswich detector, a pulse shape analysis is able to identify the various radiation signals from the three scintillators. Additionally, we find that the crystal's emission quality is maintained for a month.

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Jinyoung Kim, Yujin Lee, Byoung-cheol Koh, Chang Hyon Ha, Byung Ju Park, In Soo Lee, Hyun Su Lee. 2022-05-18. NaI(Tl) crystal scintillator encapsulated in two organic-scintillator layers with pulse shape data analysis. https://doi.org/10.1007/s40042-022-00620-w

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