I have used a scintillation counter coupled with a photo-multiplier tube to record the gamma spectra for sodium-22, cobalt-60, and Cesium-137.
I need to know how to assess the linearity of the photo-multiplier tube that I used. The photo-multiplier tube is in pulse mode, and multichannel pulse-height analysis is used in the process.
I already know that the pulse linearity in pulse mode is chiefly dependent on the peak signal current, and that the linearity is limited by the space charge effects in pulse mode. However, I still do not know how to assess the linearity in pulse mode, given the data I have.