Time eigenvalue spectrum for one-speed neutron transport in spheres with strong forward-backward scattering

The spectrum of time eigenvalues has been studied for one-speed neutrons in spheres with strong forward and backward scattering together with isotropic scattering. It is shown that in the presence of strong backward scattering there are both discrete eigenvalues and a con-ʹ tinuum of eigenvalues. The lower limit of the continuum has been determined. The results are supported by numerical calculations