Engineering topics
Publications and source records attributed to Cristancho, F.
Extreme Value theory seems to be a promising tool for analysing experimental continuum gamma decay spectra in order to obtain physical parameters at high excitation energy.
Transmission and backscattering of {gamma}-rays have been used to study soil properties such as its porosity, hydraulic conductivity and also for the detection of organic material buried in soil. These applications require a deeper understanding of the interaction of {gamma}-rays with soil. In the present work a study of the interaction of 511 keV {gamma}-rays with layers of sand varying both its humidity and thickness is presented. The experimental set-up uses the positron decay of a {sup 22}Na source, and two gamma detectors connected in fast time-coincidence. Both transmitted and backscattered spectra are obtained. For transmission, the photopeak and the low angle scattered photons are studied, and for backscattering we analyze the number of single and multiple backscattered photons as a function of thickness. Finally, a theoretical model for the derivative of the number of backscattered photons as a function of depth is presented.
A gamma Compton backscattering device is presented. It is shown that by fine-tuning several electronics parameters an image of recognizable geometry is obtained.
Buildup is studied for water and for sand with different humidity contents as a function of the thickness of the sample. A piecewise linear dependence is observed.