METHODS OF DEFINING THE NUCLEUS NECK RADIUS AT THE POINT OF RUPTURE

A comparative analysis of methods for determining the radius of the nuclear neck radius ( neck) at the point of its rupture during actinide fission is presented. Classical approaches based on the liquid drop model, modern methods of the density functional theory with time dependence and the Born-Oppenheimer approximation are considered. An alternative method based on the concept of "cold" fission with an analysis of the spin distributions of fragments is proposed. A quantitative relationship between the neck radius and the spins of fragments through transverse bending and wriggling oscillations is established. It is shown that for 235U, 238U and 252Cf the neck radius is 1.5 – 2.2 fm, which is consistent with various theoretical approaches.