Enhanced d(d,p)t fusion reaction in metals

The electron screening in the d(d,p)t reaction has been studied for the deuterated metal Pt at a target temperature T = 20 ±C to 340 ±C, and for Co at T = 20 ±C and 200 ±C. The enhanced electron screening decreases with increasing temperature, where the data agree with the plasma model of Debye applied to the quasi-free metallic electrons. The data represent the ¯rst observation of a temperature dependence of a nuclear cross-section. We also measured the screening e®ect for the deuterated metal Ti (an element of group 4 of the periodic table) at T = ¡10 ±C to 200 ±C: above 50 ±C the hydrogen solubility dropped to values far below unity and a large screening e®ect became observable. Similarly, all metals of groups 3 and 4 and the lanthanides showed a solubility of a few percent at T = 200 ±C (compared to T = 20 ±C) and a large screening became also observable. Within the Debye model the deduced number of valence electrons per metallic atom agrees with the corresponding number from the Hall coe±cient, for all metals investigated.