The analytical representation of the fundamental mode in 1-D-geometry for the CANDLE burn-up phenomenon

The fundamental mode of a CANDLE burn-up wave, propagating into fertile material, in one-dimensional geometry was derived analytically with the result that the fluence and the neutron flux shapes turned out to be a Gudermannian and a Secans Hyperbolicus, respectively, of a Galilean variable. Furthermore, the fundamental evolution equation for the neutron flux was represented and discussed thoroughly. All other higher dimensional cases, however, have to be treated by numerical methods. (orig.)