A novel approach to normalize Compton profiles of pure incoherent scatterers

Abstract

-In this paper we show that the effective atomic number of amorphous materials which can be treated as pure incoherent scatterers can itself be used as a constant for normalizing the experimental Compton profiles. This finding is expected to be useful since calculation of the normalization constant by the usual procedure of integrating the Biggs et al. Compton profile values is a tedious task for composite materials. This method is applicable to pure incoherent scatterers of known as well as unknown composition.

Determination of the effective atomic number: A theoretical justification

“…Later in 1998, Kahane [20] provided a relation between the normalization constant obtained from integrating the Compton profile with that of the incoherent scattering function S(q, Z). In our recent paper in EPL [21] we have shown that this constant itself is Z eff for pure incoherent scatterers and an experimental support for this has been provided in another paper recently published by us elsewhere [22]. This would in fact pave a way towards interpreting Z eff through a fundamental theoretical basis.…”

“…It is known that [4,21,24] for pure incoherent scatterers the incoherent scattering function is nothing but Z eff , i.e., S(q, Z) = Z eff .…”

Characterization of some stone samples of archaeological interest via Compton profile analysis

“…Algorithm of our approach to determine the normalized Compton profile [13] demands the determination of SDCS as the first step. So, SDCS values have been measured for 241 Am gamma rays at a scattering angle 120 • using a goniometer assembly with a collimator type geometry.…”

“…The K shell binding energy of the constituent elements ples is as given in Table 1. It can be noticed from the table that the Compton shift far exceeds the binding energy of the constituent elements of the stone samples so that these samples can be considered to be pure incoherent scatterers [13,22]. Hence, the normalized Biggs et al Compton profile [15] of each relavant orbital of the constituent element of the stone samples of interest was calculated and these values have been combined using mixture rule [16].…”

“…In the case of archaeological samples such as the stones of our interest it is difficult to obtain their composition information without spoiling their pristine form. In this work, we seek to resolve this problem by using an approach described in our recent papers [13,14], where in it is suggested that the effective atomic number ( Z eff ) of such composite materials which can be treated as pure incoherent scatterers will represent the number of electrons that participate during interaction with the incident photons and hence can serve as the constant for normalizing the experimental Compton profiles. Clearly this would help in preserving the pristine and original form of the material, since Z eff can be determined without hampering the same.…”