P - even T-odd asymmetries in the differential cross sections of fission reactions of unor-iented nuclei by cold polarized neutrons with the emission of prescission and evaporative light particles

Differential cross sections ${d\sigma _{nf,p}} \left(\theta\right/)d\Omega$ of the fission reaction of nonoriented target nuclei by cold polarized neutrons with the emission of light particles ($p$), which include prescission $\alpha$- particles and evaporative neutrons and $\gamma$-quanta, can be represented as the sum of the cross section ${d\sigma}^{0} _{nf,p}} \left(\theta\right/)d\Omega$, corresponding to unpolarized neutrons and the cross section ${d\sigma}^{1} _{nf,p}} \left(\theta\right/)d\Omega$, linearly related to the neutron polarization vector $\mathbf{\sigma}_n$.. The last cross section is expressed through the sum of P-even T-odd triple $A\left(\boldsymbol\sigma_{n} \left[\mathbf{k}_{LF} ,\mathbf{k}_{p} \right]\right)$ and quinary $B\left(\boldsymbol\sigma_{n} \left[\mathbf{k}_{LF} ,\mathbf{k}_{p} \right]\right)\left(\mathbf{k}_{LF} ,\mathbf{k}_{p} \right)$ scalar correlators, the signs of which change and do not change during the transformation $\theta \to \pi -\theta $ accordingly. Using the experimental cross sections ${d\sigma _{nf,p} (\theta)/ d\Omega} $ and ${d\sigma _{nf,p}^{0} (\theta)/ d\Omega} $ , the experimental values of the correlators considered above were found. In the work within the framework of the quantum theory of fission, taking into account the Coriolis interaction of the total spin of a compound fissile system with the orbital angular momenta of fission fragments and prescission $\alpha$-particles, it was possible satisfactory to describe the characteristics of the noted above experimental correlators in the case of the emission of prescission $\alpha$-particles and prompt neutrons and $\gamma$-quanta for most of the nuclei-targets under consideration. A noticeable discrepancy between the theoretical and experimental characteristics is observed for the triple correlator only in the case of $\alpha$-particles for the target nucleus $^{233}$U. This, apparently, can be associated with an additional mechanism of the appearance of similar correlators, connected with the influence of bending and wriggling--oscillations of compound nucleus in the vicinity of the scission point on $\alpha$-particle escaping from the nucleus neck.