The Role of the Density of the Crown Group of Optical Glasses in the Formation of Their Quantitative Characteristics of X-Ray and Gamma Radiation Attenuation

Abstract

The dependence of the linear coefficients of X-ray and gamma radiation attenuation (LCRA) is studied in the energy range of quantum energies, E, from 0.2 to 3.0 MeV by optical glasses of the crown group on their density when it changes from 2.21 to 4.61 g/cm³. Both the published data on the LCRA of glasses and the data obtained in this study are used as the basis for this paper. For this, the values of the mass coefficients of radiation attenuation (MCRA) of oxides used in the production of crown glasses are calculated. It is established that the basic oxides (SiO₂, B₂O₃, P₂O₅, Na₂O, K₂O, CaO, ZnO, Al₂O₃), which are included in all types of crown glasses (LK, K, FK, TFK, BK, TK, STK) are characterized by a relatively weak dependence of MCRA on E. In contrast, the heavier oxides (PbO, Ta₂O₅, La₂O₃, BaO, CdO, Y₂O₃, ZrO₂), used to obtain BK, FK, TFK, TK, and STK glasses of certain grades, demonstrate a strong dependence of MCRA on E in the energy range from 0.2 to about 1.0 MeV, but in the region of the more high energy quanta, close to that for basic oxides. It is shown that for E values of 0.2, 0.3, 0.4, 0.5, 0.6, 0.8, 1.0, 1.5, 2.0, and 3.0 MeV, the LCRA values for a wide range of glasses of the crown group are clearly described by linear dependencies on density, whose inclination angles decrease with the growth of E. Equations describing these straight lines are derived, which make it possible to accurately calculate the LCRA of glasses from their density. At the same time, with the E values changing from 0.2 to 0.4 (0.5) MeV, some glasses of the BK, TK, and STK types have lower LCRA values than those which would be expected if their LCRA values were located on these lines. These deviations are explained by the difference in the nomenclature and concentrations of heavy oxides in these glasses and in the glasses closest to them in density whose LCRA values fit well on the straight lines. For these glasses, at E ranging from 0.6 to 3.0 MeV, no deviations of the LCRA values from straight lines are observed.