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07 September 2008

Answer to Question #5992 Submitted to "Ask the Experts"

Category: Radiation Basics — Beta Particles (negative and positive) and Electrons

The following question was answered by an expert in the appropriate field:

Dear Sirs, I have downloaded the beta spectral data DEXRAX code as well as RADTOOLBOX provided by several Web sites. In these two codes it is possible to view beta spectrum frequencies with respect to predetermined energy grids. The codes quote that the spectrum is given in the form of E vs Y(E)dE and give the unit of N(E)/MeV/Bq s. I have determined efficiencies for commonly available beta sources carbon-14, cobalt-60, thallium-204, RaD+E (lead-210 plus bismuth-210), and strontium-90/yttrium-90 with different thickness absorbers. Now I want to determine the efficiency of the counting system for various energy groups. Kindly let me know how to unfold the beta spectrum so that I can get N(E)/disintegration. I tried multiplying the difference of consecutive energy grid points, but when I sum the intensities together I always get 1.04 something instead of 1. I don't know where I am making the mistake. Kindly guide me.

Download the following Portable Document Format file to complete the answer to your question: q5992.pdf

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