Effective atomic numbers of some H-, C-, N- and O-based composite materials derived from differential incoherent scattering cross-sections

Abstract

In this work, we have made an effort to determine whether the effective atomic numbers of H-, C-, N-and O-based composite materials would indeed remain a constant over the energy grid of 280-1200 keV wherein incoherent scattering dominates their interaction with photons. For this purpose, the differential incoherent scattering cross-sections of Be, C, Mg, Al, Ca and Ti were measured for three scattering angles 60 • , 80 • and 100 • at 279.1, 661.6 and 1115.5 keV using which an expression for the effective atomic number was derived. The differential incoherent scattering cross-sections of the composite materials of interest measured at these three angles in the same set-up and substituted in this expression would yield their effective atomic number at the three energies. Results obtained in this manner for bakelite, nylon, epoxy, teflon, perspex and some sugars, fatty acids as well as amino acids agreed to within 2% of some of the other available values. It was also observed that for each of these samples, Z eff was almost a constant at the three energies which unambiguously justified the conclusions drawn by other authors earlier [Manjunathaguru and Umesh, J. Phys. B: At. Mol. Opt. Phys. 39, 3969 (2006); Manohara et al, Nucl. Instrum. Methods B266, 3906 (2008); Manohara et al Phys. Med. Biol. 53, M377 (2008)] based on total interaction cross-sections in the energy grid of interest.

Assessment of methods for estimation of effective atomic numbers of common human organ and tissue substitutes: waxes, plastics and polymers

“…The experimental values of the effective atomic numbers of PP, BK and ER (Parthsaradhi et al, 1992;Shivaramu et al, 2001;Ashok et al, 2007;Prasanna et al, 2010;Kucuk et al, 2013) in the Compton scattering-dominated region shows that the computed values in the present work are comparable. It is to be noted from the graphs that the effective atomic numbers in Compton region calculated by the direct and interpolation methods are in very good agreement.…”

“…It is to be noted from the graphs that the effective atomic numbers in Compton region calculated by the direct and interpolation methods are in very good agreement. In the case of TF, the effective atomic number values are slightly distant from the calculation (Parthsaradhi et al, 1992;Prasanna et al, 2010). The reasons for this difference may be due to incoherent scattering cross-sections used for derivation of effective atomic numbers at the mentioned photon energies.…”

“…Several authors have reported the effective atomic numbers for gaseous mixtures (Singh and Badiger, 2012), alcohols (Singh and Badiger, 2013), composite materials (Prasanna et al, 2010), solutions (Kulwant et al, 2001), dosimetric materials (Kiran and Venkata, 1997) and biological materials (Koç and Özyol, 2000;Shivalinge et al, 2005;Manjunathguru and Umesh, 2006;Demir et al, 2012). This study will be helpful for additional information and deciding the appropriate method for computation of the effective atomic numbers analogous to the experimental values.…”

Experimental measurement of effective atomic number of composite materials for Compton effect in the γ-ray region 280–1115 keV by a new method

“…The differential incoherent scattering cross-sections of the inorganic compounds of interest in the present work were obtained using the scattered intensity, source strength and the geometry factor by adopting a procedure similar to an earlier work carried out in our laboratory [1,3].…”

“…Recently [1], we have reported the effective atomic number, Z eff , for Compton effect of some H-, C-, N-and O-based composite materials in the energy range 280-1200 keV. These values have been determined from a mathematical relation, which is based on the measured differential incoherent scattering cross-sections of elements of atomic number in the range 4-22.…”