Andrea Lavagno (Politecnico di Torino) Gianpiero Gervino (Università di Torino)
The recent important experiment on neutron reaction on $^7$Be of n_TOF at CERN has shown that the “$^7$Li problem” is still not solved. In the recent past we have shown that small deformations of the tails of distribution functions of ions in stellar plasma produce sensible enhancements or depletions of the nuclear fusion rates. The astrophysical environment influences the nuclear reactions (through, for instance, space and time nuclear correlations). These effects can be taken into account by means of a deformed statistics featured by an entropic parameter, the deviation from its standard value is responsible of deformations of the distribution functions and therefore of nuclear rates enhancement or depletion. A recent investigation has recently shown that the “$^7$Li problem” could be solved adopting a generalized statistical distribution (arXiv:1412.6956). In this work we want to make evident the physical meaning of the entropic parameter in astrophysical plasma where $^7$Li is produced or destroyed and to show how nuclear fusion rates of interest in this problem can be evaluated (with the use of LUNA of Gran Sasso Lab experimental results) toward a “$^7$Li problem” solution.
Piero Quarati (Politecnico di Torino)