The effect of the matrix condition number on the estimate of core barrel motion

It is shown, that the matrix condition number plays determining role in the error of estimation of core barrel motion when using the well known spectral decomposition methods. Matrix condition numbers were estimated for different type of reactors and detector arrangements. It is shown that in unfortunate case the statistical error of estimate can reach hundreds of the original statistical error. It is suggested to eliminate one of the freedom of the system, before making spectral decomposition, which can drastically improve the accuracy of the decomposition.