Gamma Shielding and Dosimetry Parameters of Sodium-Silicate Glasses with Significant Role of TbF3 Addition

Tb 3+ -doped sodium-silicate glasses, chemically defined as (73.2SiO 2 -15.3Na 2 O-6MgO-2ZnO- 3.5CaO) 1-x -(TbF 3 ) x for x = 0, 5, 7, 9, 11, 13, and 15 wt%) were theoretically investigated for their radiation shielding and dosimetry potentials. The photon interaction parameters were estimated using the NIST-XCOM computational tool. The obtained results showed that the attenuation coefficient of the sodium-silicate glasses decreased from 7.2062 to 0.0210 cm 2 /g for x = 0, 10.5553 to 0.0221 cm 2 /g for x = 5 mol%, 11.8949 to 0.0225-cm 2 /g for x = 7 mol%,, 13.2346 to 0.0229cm 2 /g for x = 9 mol%, 14.5742 to 0.0233 cm 2 /g for x = 11 mol%, 15.9138 to 0.0238 cm 2 /g for x = 13 mol%, and 17.2534 to 0.0242 cm 2 /g for the x = 15 mol% sample, respectively, for γ-photon energy increase from 15 to 15,000 keV. For the same sample order, the mass energy absorption coefficient varied from 0.0161 to 7.4884, 0.0167 to 10.5009, 0.0169 to 11.7058, 0.0171 to 12.9108, 0.0174 to 14.1158, 0.0176 to 15.3208, and 0.0176 to 16.52582 cm 2 /g. The effective atomic number changed from 10.49 to 24.04, 10.62 to 27.69, 10.74 to 30.84, 10.87 to 33.57, 11.01 to 35.97, 11.15 to 38.10 for SNMZCT2, SNMZCT3, SNMZCT4, SNMZCT5, SNMZCT6, SNMZCT7, respectively. The minimum specific gamma constants for the investigated samples were obtained at 0.2 MeV with values of 5.435 Rm 2 /Cih, 6.102 Rm 2 /Cih, 6.770 Rm 2 /Cih, 7.437 Rm 2 /Cih and 8.772 Rm 2 /Cih for SNMZCT2, SNMZCT3, SNMZCT4, SNMZCT5, SNMZCT6 and SNMZCT7, respectively. Using the geometric fitting method, the computed buildup factors show significant variation with energy of incident gamma photons, number of glass mean free path (mfp), and the chemical composition (i.e., TbF 3 content) of the glasses. Increasing the molar concentration of TbF 3 in the glass system improves its photon shielding abilities and suppresses photon scattering in the glasses.