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arXiv · 1912.05991

Rate for Laser-Induced Nuclear Dipole Absorption

Adriana Pálffy·Paul-Gerhard Reinhard·Hans A. Weidenmüller
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Abstract

Using the Brink-Axel hypothesis we derive the rate $R$ for nuclear dipole excitation by a laser pulse carrying $N \gg 1$ photons with average energy $\hbar ω_0 \approx 5$ MeV. As expected $R \propto (\hbar ω_0)^3$. The rate is also proportional to the aperure $α$ of the laser pulse. Perhaps less expected is the fact that $R \propto N$, irrespective of the degree of coherence of the laser pulse. The expression for $R$, derived for a nearly stationary laser pulse, is valid also for short times and can, thus, be used in simulations via rate equations of multiple nuclear dipole excitations by a single pulse. The explicit dependence of $R$ on the parameters of the laser pulse and on nuclear parameters given in the paper should help to optimize experiments on laser-nucleus reactions.

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Adriana Pálffy, Paul-Gerhard Reinhard, Hans A. Weidenmüller. 2020-05-05. Rate for Laser-Induced Nuclear Dipole Absorption. https://doi.org/10.1103/physrevc.101.034619

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