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arXiv · 1609.00383

Dynamical Screening of $\alpha$-$\alpha$ Resonant Scattering and Thermal Nuclear Scattering Rate in a Plasma

Xiaojun Yao·Thomas Mehen·Berndt Müller
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Abstract

We use effective field theory and thermal field theory to study the dynamical screening effect in the QED plasma on the $\alpha$-$\alpha$ scattering at the $^8$Be resonance. Dynamical screening leads to an imaginary part of the potential which results in a thermal width for the resonance and dominates over the previously considered static screening effect. As a result, both the resonance energy and width increase with the plasma temperature. Furthermore, dynamical screening can have a huge impact on the $\alpha$-$\alpha$ thermal nuclear scattering rate. For example, when the temperature is around $10$ keV, the rate is suppressed by a factor of about $900$. We expect similar thermal suppressions of nuclear reaction rates to occur in those reactions dominated by an above threshold resonance with a thermal energy. Dynamical screening effects on nuclear reactions can be relevant to cosmology and astrophysics.

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Xiaojun Yao, Thomas Mehen, Berndt Müller. 2016-09-01. Dynamical Screening of $\alpha$-$\alpha$ Resonant Scattering and Thermal Nuclear Scattering Rate in a Plasma. https://doi.org/10.1103/physrevd.95.116002

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