Pico Tech - Equipement Test1

Radiation Detection / Theremino Mca En / English Documents

Testing some equipments

*** Please note that these are very casual tests done without proper knowledge for some equipments. ***

I've been testing some equipments I got (so that I can learn and use them in future).

I put the CsI crystal on Dumont 3 inch PMT using the optical grease, held by black electric tape,
placed inside a coffee can to keep it light tight.
I used Ortec 456 HV (as the HV on MCA doesn't turn On, yet).

I know 3 inch PMT is too big for the crystal, but I wanted to test these equipments,
and Luuk's crystal was the only one I have (other than ZnS film) to make the test.

Fortunately, everything seems to be alive, so far.

As the size of PMT and crystal isn't matched, and as I don't know the optimal setting of all components,
the result isn't pretty at all.
But at least, I got something that looks like Cs137 peak.

Printscreen of Maesto (the basic Ortec software). Upper half is linear graph and the bellow is Logarithmic.

The same spectrum shown by another Ortec graph printing utility.

I did similar test with the Dumont 3 inch PMT and Luuk's CsI crystal (22mm x 25mm) using Theremino PMT Adapter, before.

The spectrum is even more puzzling. I'm showing this as a good bad example...
I'm not sure, but it might be because of the big old PMT needing more power than Theremino PMT adapter can provide.
Also I have a feeling that this PMT has peaks that look like Thorium chain isotopes on its BG.

Although these tests don't do any justice for the excellent CsI crystal offered by Luuk, it did help me to confirm that these old things are still working.
(I'm thinking about using it with Photo diode based system or small PMT to make a small spectrometry system)

I would like to say thank you to Luuk and his boss for the crystal, grease and other things/information.
Also, I have been helped by Geo and other members of the Yahoo group, Theremino Team members, iRadic and others.

Thank you.

Last modified : Fri Dec 13 11:50:15 2013 Maintained by nkom AT pico.dreamhosters.com