Nuclear threads

The internal structure of deuterons weakly influences a motion of their center of mass (translational motion). The scenario can be different when the translational wave function has a formal singularity along the line (thread) connecting the deuteron and another Coulomb center. The singularity is cut off by fluctuations of nuclear internal degrees of freedom and the wave function becomes smooth with the narrow peak. The peak is associated with the certain potential well which is localized on the thread and dominates the Coulomb barrier. As a result, the deuteron is able to move along the thread with no classical reflection. Two deuterons can get in contact despite their energy is low. This is not an underbarrier motion but one along the region which became classically allowed due to the thread well. In experiments nuclear threads can be formed by the incident particle flux if to adjust its angular distribution at large distances.