. why plastic scintillator is more useful than other scintillator in beta decay experiment??
It depends on what you want to measure.
Did you look up the advantages and disadvantages of plastic scintillators?
I want to measure the end point energy of beta particles emitted from a radioactive source which is placed above the plastic scintillator ... yeah I am looking for the advantages of plastic scintillator in this particular case..
One reason is that the heavy Z components of an inorganic scintillator creates more backscatter than an organic which causes spectral distortion.
Then you probably want a good energy resolution, while timing resolution is not that important. Every comparison of scintillator types should cover those two things.
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