Screening Potential of ⁶Li(d,α)⁴He and ⁷Li(p,α)⁴He Reactions in Liquid Lithium

Abstract

In order to investigate the screening effect of a nuclear reaction in a liquid metal environment, thick-target yields of the 6 Li(d,) 4 He and 7 Li(p,) 4 He reactions were measured using a liquid Li target for incident energies between 22.5 and 70 keV. The modified SðEÞ factor [S Ã ðEÞ] for the liquid Li environment was deduced by dividing the measured yield by the energy integration of the penetration factor divided by the stopping power. It was shown that S Ã ðEÞ for the liquid environment is considerably larger than that for the atomic/molecular environment for both reactions. The difference in the screening energy between the two environments was deduced to be ÁU ¼ 235 AE 63 ( 6 Li+d) and 140 AE 82 eV ( 7 Li+p), although the screening energy for liquid Li has a large uncertainty with U liq $ 486{776 ( 6 Li+d) and 324-637 eV ( 7 Li+p) owing to the uncertainty of the astrophysical bare SðEÞ factors. This difference in the screening energy should be considered in such a way that, in liquid Li metal, conduction electrons and Li þ ions contribute to the screening in addition to bound electrons.

The role of correlation entropy in nuclear fusion in liquid lithium, indium and mercury

“…Analogous enhancements has been seen in fusion between accelerated deuterons on light nuclei in the target [13,14].…”

“…The total screening potential for lithium is ≈ (520 ± 190) eV against a prediction of about 71 eV [13,14];…”

“…In fact the total screening potentials measured by several groups for different gases are in the range 200 − 300 eV [13,27];…”

“…But the uncertainty on the bare cross section cancels in the difference and the percentage error is much smaller, about 35%: for instance Fang at al. [13] quote 235 ± 65 eV for the difference between the liquid and atomic/molecular phase. As a reference typical value we use 200 ± 70 eV.…”

Negentropy in Many-Body Quantum Systems

“…Fusions in liquid metals and entropic correlations: the Tohoku group has measured a different effective screening potential in solid and liquid lithium, and we have recently proposed that the two-body correlation gives a negative contribution to the entropy that could explain the different screening between solid and liquid metal [38] (additional details and results from the experiments of interest can be found in [39][40][41][42][43]). …”