DIY Scintillation probe: 63x63mm NaI(Tl)

Some time ago I’ve won a 63×63 NaI(Tl) crystal for around 80€ at eBay. It is an SDN52 a special crystal designed to be heat and vibration resistant. Let’s build a probe with it and a 76mm photokatode XP2421/SQ PMT

63×63 Scintillator

First problem to solve was how to tightly couple this heavy crystal with this PMT? I’ve solved it with the help of my 3D printer: I’ve designed and printed a fitting with TPU that’s a kind of rubber filament material. STL zip file: gasket  password: madexp

And now let’s put all togheter.


The crystal

The assembly

Finally I’ve soldered in place the dynode chain voltage divider PCB.


After covering the tube with black tape I am ready to test it.

The result is a nice 7.5%-8% FWHM @ Cs137 peak