1.5"*1.5" NaI side well 1000v 50lb lead. peak at 2.46MeV when empty?

[comoxboy]

Hello I'm just starting out and was able to calibrate fine but my baseline has a peak at 2.46MeV and I don't know what it could be.

[Sesselmann]

Colin,

Hi and welcome to the forum. (a formal intro would be nice.)

Regarding your question, a picture would be worth a thousand words, so maybe you can upload a screen clipping. Remember to include the settings panel.

You are using a 1.5" detector with a well, as such the crystal has pretty low stopping power, I doubt you are seeing any peak at 2614 keV, which is one of the naturally occurring peaks from Ti-208.

I suspect it may be the pile up at 100 arb.u resulting from the volume being too high. A good rule of thumb for the volume setting is to set your K40 peak to 50 arb.u. (middle of the scale).

Steven