Sources of Uncertainties in Neutron Radiography

The method of neutron radiography is simple to implement. Since water has a large neutron attenuation coefficient, the technique of radiography has a high sensitivity for small water mass changes [Pg.187]

The water thickness measurement uncertainty due to neutron counting statistics can be calculated from Poisson counting statistics. For a random process, the standard deviation, Ah in the observed counts I is A/ = y7. The number of neutrons in the incident, or open beam, I0, is the product of the neutron fluence rate (cur2 s 1), integration time T (s), integration area A (cm2), and neutron detection efficiency, ip [Pg.188]

Changes in the Total Neutron Scattering from Water Absorbed in the Membrane [Pg.191]

A large potential source of systematic uncertainty is due to the finite image resolution. The measured image can be described as the convolution of the true sharp image with the imaging system point spread function, PSF. The PSF is reasonably approximated by a Gaussian, [Pg.192]

This means that if the total water content of the test section is measured from the image [Pg.194]