9B20.30 - Photomultiplier tubes and NaI Crystals

See paragraph one in the procedure section.
Code Number:
Demo Title:
Photomultiplier tubes and NaI Crystals
Area of Study:
Modern Physics
Photomultiplier Tubes, NaI Crystals, Mu-Metal Shields.

See also 9B20.30 in Modern Physics.

The NaI crystals should be kept in a reseal able plastic bag to prevent water absorbing into and degrading the crystals. The Mu-Metal shields are made of a special alloy that helps prevent the penetration by magnetic fields. These are used routinely around photomultiplier tubes as magnetic shields.

  • P. Venkataramaiah, H. Sanjeeviah, and B. Sanjeevaiah, "Energy Dependence of the Relative Halfwidth of Gamma-Ray Lines in NaI (TI) Crystals - A Laboratory Experiment", AJP, Vol. 46, # 3, Mar. 1978, p. 292. 
  • John H. Moore, Christopher C. Davis, Michael A. Coplan,  "Photoemissive Detectors",  Building Scientific Apparatus 2nd Edition,  pp. 260 - 271.
  • Stilbene Crystal, "A Crystal That Detects Nuclear Radiation (No, Really), Popular Science, Dec. 2015.

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