# Gamma ray detector resolution

Trying to understand the resolution in the context of the standard error of the mean. An example in a book reads: "The energy resolution of a gamma ray detector used to investigate a decaying nuclear isotope is 50keV. If only one such decay is observed its energy is known to 50keV. If 100 are collected this improves to 5keV. To reach 1keV you would need to observe 2500 decays."

I understand that the standard error of the mean falls off like 1/sqrt(N). But I'm confused how this relates to the intrinsic resolution of the detector. Isn't its resolition a set thing? (Sorry I know I sound clueless, I think I actually am).

What determines the resolution of the detector for a single measurement? How can (why) this intrinsic property change as your sample number increases?

It all sounds to me like "your phone can take pictures of resolution x. If you take many pictures the resolution will improve".

Please don't assume prior knowledge of any kind in your answer (if that is possible at all).

• They would appear to be sloppy, and not considering the detector resolution. Nov 16, 2016 at 20:33
• If you take many pictures the resolution will improve is kinda the premise behind lucky imaging (though the resolution is improved with post-processing of a multitude of images) Nov 16, 2016 at 20:35