ABOUT SOLVING THE INVERSE NEUTRON-ACTIVAT ION LOGGING PROBLEM WITH THE EMPLOYMENT OF EFFECTIVE MEDIA NUCLEAR-PHYSICAL PARAMETERS

A new method to solve the inverse neutron activation logging problem i s discussed. In this method the specific gamma-ray intensity K is dete rmined for the same real media the value of gamma-ray intensity of all activated atoms of mineral is measured. The determination is based on the knowledge about effective nuclear-physical parameters. It is stat ed that the knowledge about these three parameters - bulk density rho , slowing-down length for fast neutrons L and lifetime for thermal ne utrons tau - is enough to solve the problem and the connection K with them is: K(L, tau*, rho*) = (a + b . tau*) . e(c . rho* + d . L*), w here a, b, c, d are the coefficients determined by test measurements f or a limited number of samples. The results obtained by this method in bauxite and copper are shown.