  Fission-fragment properties have been calculated for thermal neutron-induced
fission on a $^{239}\textrm{Pu}$ target, using constrained
Hartree-Fock-Bogoliubov calculations with a finite-range effective interaction.
A quantitative criterion based on the interaction energy between the nascent
fragments is introduced to define the scission configurations. The validity of
this criterion is benchmarked against experimental measurements of the kinetic
energies and of multiplicities of neutrons emitted by the fragments.
