Determination of X-ray mass attenuation coefficients using HPGe detector

Area of Science:

• Nuclear Physics
• Materials Science
• Radiation Detection

Background:

• Accurate determination of mass attenuation coefficients is crucial for radiation shielding and dosimetry.
• Previous methods required refinement to account for geometric and detector-specific factors.

Purpose of the Study:

• To present a detailed and optimized method for measuring the mass attenuation coefficient (mu(m)) of low-energy X-rays.
• To validate the method using standard reference materials like aluminum and nickel.
• To compare experimental results with theoretical values for various elements and biological equivalents.

Main Methods:

• Utilized a High-Purity Germanium (HPGe) X-ray detector and radioactive sources.
• Employed an optimized geometry with a specific source-detector distance.
• Selected absorber foils and counting times based on detailed investigations for optimal mu(m) determination.
• Measured photon intensity by gating the spectrometer channel at FWHM/photo peak.

Main Results:

• Identified an optimal transmission (T) range (0.5 >= T >= 0.02) for obtaining the best mass attenuation coefficient values.
• Successfully measured mu(m) for Magnesium, Nickel, Copper, Molybdenum, and Tantalum.
• Obtained comparable measurements for three biological equivalent materials.

Conclusions:

• The developed method provides accurate mass attenuation coefficient values for low-energy X-rays.
• The findings support the use of specific absorber thicknesses for reliable mu(m) measurements.
• Experimental results show good agreement with standard theoretical values, validating the method's efficacy.