An improved Compton scattering method for determination of concentration of solutions

Gamma backscattering analysis of flaw types and orientation based on Monte Carlo GEANT4 simulations

In this study, we modeled the effects of flaws in a solid material as three different slit types (rectangular, rectilinear, and semicircular) and their orientations in a duralumin (aluminum alloy) plate in simulations based on 137Cs gamma backscattering. The simulations were performed using the Monte Carlo GEANT4 simulation toolkit. The simulation results showed that the shape of the slit had a small effect on the backscattering peak curve. Rotating the slit on the Y-axis and Z-axis of the duralumin plate influenced the 137Cs backscattering peak height in the energy range from 0.185 to 0.20 MeV, where the backscattering peak areas exhibited specific patterns due to the slit orientations.

A method for determination mass absorption coefficient of gamma rays by Compton scattering

A method was proposed for determination mass absorption coefficient of gamma rays for compounds, alloys and mixtures. It is based on simulating interaction processes of gamma rays with target elements having atomic numbers from Z=1 to Z=92 using the MCSHAPE software. Intensities of Compton scattered gamma rays at saturation thicknesses and at a scattering angle of 90° were calculated for incident gamma rays of different energies. The obtained results showed that the intensity of Compton scattered gamma rays at saturations and mass absorption coefficients can be described by mathematical formulas. These were used to determine mass absorption coefficients for compound, alloys and mixtures with the knowledge of their Compton scattered intensities. The method was tested by calculating mass absorption coefficients for some compounds, alloys and mixtures. There is a good agreement between obtained results and calculated ones using WinXom software. The advantages and limitations of the method were discussed.

Gamma photon techniques for detection of nucleation in superheated emulsion detectors for neutron dosimetry

Application of transmission and scattering gamma photon techniques for calibration of superheated emulsion detectors used for neutron dosimetry is described. The bubbles nucleated in the detector due to neutron exposure generate detectable changes in both attenuation and scattering properties of the medium, and the magnitude of change in properties depends on population density of bubbles nucleated and in turn is proportional to neutron dose. The experimental set-up consists of (137)Cs and (241)Am sources and an HPGe detector-based gamma-ray spectrometer. An indigenously developed bubble detector and a commercially available one (BTI, Canada) are used in the present study. Theoretical models for the variation in transmitted and scattered intensities through the bubble detector as a function of neutron dose are formulated, and the experimental results obtained are found to be in good agreement with the models. In the neutron dose region studied, the transmission technique shows better sensitivity than scattering technique.