Linear amplifier question, Coarse Gain/Fine Gain.

AI Thread Summary
In a spectroscopy lab using a scintillator and Cs-137, the user calibrated the spectrum at 662 Kev but faced challenges when adjusting settings for a Co-60 spectrum. The coarse gain was set to x16 for Cs-137 and x8 for Co-60, while the fine gain changed from x5 to x3.5. The user seeks to understand how to factor in the fine gain adjustment when correlating energy levels to channel numbers. It is noted that there is no standard answer for these adjustments, and consulting the equipment manuals is recommended for specific guidance. Accurate calibration is essential for obtaining reliable spectral data.
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I'm currently doing a spectroscopy lab where you use a scintillator and Cs-137 to obtain a Cs-137 spectrum. I calibrated this spectrum using the known gamma energy for Cs-137 at 662 Kev at the photo peak. I am now trying to use this calibration for a Co-60 spectrum. The problem is that when I obtained my Cs-137 Spectrum I had the coarse gain at x16 and fine gain at x5. When I was taking data for the Co-60 I had to adjust the coarse gain to x8 and fine gain to x3.5. I understand the coarse gain is half that of the Cs-137 but how would I factor in the fine gain? For example for Cs-137 the photo peak was on channel 935 at 662Kev. So if I adjust the gain by half then 662Kev should correspond to channel 467.5 for the Co-60 spectrum. How does the fine gain adjust the factor?
 
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You are going to have to resort to the manuals for the equipment you are using. There is no "standard" answer.
 
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