München 2019 – wissenschaftliches Programm
HK 54.32: Poster
Donnerstag, 21. März 2019, 16:30–19:00, Foyer Theresanium
Plasma screening effects in laser-generated plasmas — •David Elsing, Adriana Pálffy, and Yuanbin Wu — Max-Planck-Institut für Kernphysik, Heidelberg
In hot and dense astrophysical plasmas, the reaction rate of nuclear reactions is modified by the plasma screening. Direct measurements of this effect in the laboratory, which would be vital for our understanding of nuclear processes occuring in stellar nucleosynthesis, remain until today very challenging. Upcoming petawatt laser facilities, such as the Extreme Light Infrastructure, could render such measurements possible, allowing the comparison of several theoretical models to experimental data .
Here we investigate theoretically four plasma screening models with focus on the quantum mechanical model  which we extend to low temperatures and laboratory conditions. The reactions considered are 13 C (α,n) 16 O, which is important in advanced stellar phases and in the s-process, as well as 7Li (d,α) α, which is relevant in the big bang nucleosynthesis. Our results show a rather large discrepancy between the investigated models at low temperatures and high densities.
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