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arXiv · 1202.3309

Imaginary-time method for radiative capture reaction rate

Kazuhiro Yabana·Yasuro Funaki
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Abstract

We propose a new computational method for astrophysical reaction rate of radiative capture process. In the method, an evolution of a wave function is calculated along the imaginary-time axis which is identified as the inverse temperature. It enables direct evaluation of reaction rate as a function of temperature without solving any scattering problem. The method is tested for two-body radiative capture reaction, ${^{16}{\rm O}}(\alpha,\gamma){^{20}{\rm Ne}}$, showing that it gives identical results to that calculated by the ordinary procedure. The new method will be suited for calculation of triple-alpha radiative capture rate for which an explicit construction of the scattering solution is difficult.

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Kazuhiro Yabana, Yasuro Funaki. 2012-02-15. Imaginary-time method for radiative capture reaction rate. https://doi.org/10.1103/physrevc.85.055803

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