Gamma Spectrometry Forum

Okay. If we order the intervals one after the other, the count will be 1 (one) for each interval. It will give us a single frequency of one for each lifetime value, that is a flat frequency (probability) function. Each value will be unique, which gives us no information on the expected lifetime. Bin...

With Pieters set-up, we measured muon lifetime in 156 oscilloscope images, that is, time between doublets. The expected lifetime is about 2.1 microseconds (2.2 in free space, but somewhat lower in a scintillator). Since the oscilloscope was set with a maximum delay of 9 microseconds between pulses, ...

Ok Steven. I wasn't sure where to put it, precisely because it is different. Now I have edited the first page, putting it last, added explanations. I think that it summarizes the nature of the experiment and its results in an efficient way.

A supplement to previous post, viewtopic.php?f=5&t=72, 2D plot of coincidence spectra of Compton scattering of Cs-137 gamma 662 keV.

Yes. I wrote my last comment without first taking note of your and Pieter's last comments. After submitting it, I realized that there was a second page with your last comments, coming to a conclusion. Still, since I like statistics, I let it be. Agree. This is a very interesting area.

Hello. I am not sure that I see the problem that you see Steven, but I will give it another try. If the energy transfer in the plastic detector is not sufficient, random coincidence will be (much) larger than any systematic coincidence. A coincident spectrum due to random coincidence is identical wi...

Yes. I asked myself the same thing in the beginning. Why this huge difference between the spectra at 0 degrees and the other ones? If I remember right, I and Pieter talked about it briefly, but I am not sure what ge said. Anyway, this is how I see it now. At 0 degree, gamma-photons pass (almost) rig...

Yes. A very good, instructive visualisation.

Yes. The source is Cs-137. The dedectors are fixed, shielded, small openings facing each other. The source is positioned around the plastic detector, with a small opening facing the source.
Tom

Using Cs-137, plastic detector (unknown spec), NaI detector, PRA and external sound card Asus Xonar U7 (24 bit & 192 kHz), I studied - with a lot of support from my professor Pieter Kuiper - the coincident spectra of electron and photon energies at angles 0, 30, 60, 90, 130 and 160 degrees. The ...