Nuclear problems in astrophysical q-plasmas and environments

Abstract

Experimental measurements in terrestrial laboratory, space and astrophysical observations of variation and fluctuation of nuclear decay constants, measurements of large enhancements in fusion reaction rate of deuterons implanted in metals and electron capture by nuclei in solar core indicate that these processes depend on the environment where they take place and possibly also on the fluctuation of some extensive parameters and eventually on stellar energy production. Electron screening is the first important environment effect. We need to develop a treatment beyond the Debye-Hückel screening approach, commonly adopted within global thermodynamic equilibrium. Advances in the description of these processes can be obtained by means of q-thermostatistics and/or superstatistics for metastable states. This implies to handle, without ambiguities, the case q < 1.

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

“…The gain can be calculated by using the modified Debye-Hückel approach. Furthermore the deuteron collision frequency is increased because of the energy-momentum uncertainty (GalitskiYakimets quantum effect) [20]. Solid lithium has the ions localized in the crystal; the entropy of the crystal is practically the sum of one-body contribution S 1 (kinetic energy) plus very minor contributions from many-body correlations, from atomic electron cloud and from quantum effects.…”

“…where E k is the kinetic energy of the deuteron inside of the metal reduced by the stopping power, whose value can be calculated following the approach explained in detail by Coraddu et al [20]. Since the two-body correlation melting entropy is always negative (correlations give order to the system) in a liquid metal, E k = E + ∆E = E −E cage > E.…”

“…Other authors [20,22,39] point out that, as a result of frequent collisions of particles in environments like metal matrices or dense plasmas, the complete correspondence between total and kinetic energy disappears and the distribution function depends both on total and kinetic energy with visible effect on its tail. Momentum distribution is fundamental for the fusion reaction rates and deviations from Maxwellian distribution play a central role.…”

“…We have suggested explanations [20] of the effective potential for fusion in solid metal matrices based on: 1) modifications of the Debye-Hückel approach by spatial fluctuations of the DebyeHückel radius;…”

Screening Effects in Stars and in the Laboratory

“…The Debye model predicts a characteristic temperature dependence of the screening proportional to T 1/2 which was tentatively observed in [91]. Considering the ion-momentum distribution and inhomogeneous screening effects beyond the Debye model reduced the gap between prediction and observation [92,93]. The Debye model was, however, questioned in [89].…”