Low Energy Nuclear Fusion Reactions in Solids

The DD fusion reactions in various materials have been studied, and enhancements in the rate of the D(d,p)T fusion reaction over the Gamow function were clearly seen in the materials. Of particular interest is the fact that the reaction rate of the D+D reactions at 2.5 keV in PdO is 60 times (and in Pd 10 times) larger than in Ti, and the deduced screening energy amounts to 600 eV (300 eV). Furthermore, the subsequent study on the Li+d reactions showed large screening energy as 1.7 keV, again, in Pd metal. These cannot be explained by bound-electron screening which may give at most an energy of 20 eV for the DD reaction and of 0.3 keV for the Li+d reaction, but suggests the existence of an additional, and important, mechanism. Perhaps there is a fluidity of deuterons in metals that also reduces the Coulomb barrier between the fusing nuclei.