FORMAL THEORY OF NEUTRON-INDUCED FISSION

General expression for differential cross section of neutron induced f ission is derived with account of arbitrary spin orientation of collid ing particles. A covariant description of angular dependence of fissio n cross section is proposed. Helicity representation for fission fragm ents is considered in details and limits of its validity are investiga ted. It is shown that this representation makes reliable basis for des cription of interference effects in total and differential cross secti ons of fission induced by slow neutrons. A relation between total frag ment helicity (K) over tilde and A.Bohr quantum number K is discussed.