Some factors should be considered in selecting a crystal scintillator type inγlogging and n-γlogging.In this paper

spectra of 0.662 and 6.13 MeVγ-rays using NaI

BGO and LaBr

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scintillators are simulated with an M-C code

so as to compare theirγ-ray energy deposition spectra and detector responses

and analyze the detector parameter effects on the spectrum.The results show that in the low energy region

the detector length and diameter have greater effect on detection efficiency of BGO than that of NaI and LaBr

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and the diameter effect on the detection efficiency is greater than that of the length.In high energy region

the detector size effect is small

and the crystal diameter affects less than the crystal length.Among the three types of crystal scintillators

BGO has the greatest detection efficiency

and the highest intensity in terms of the full energy peak and backscattering peak in low energy region

and photon peaks and the first-escaping peak in high energy region.