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arXiv · 2403.08608

Nuclear coherent $\pi^0$ photoproduction with charge-exchange and spin-flip rescattering

Viacheslav Tsaran·Marc Vanderhaeghen
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Abstract

In this work, we present an updated model for nuclear $\pi^0$ photoproduction, which incorporates pion second-order rescattering on intermediate excited nuclear states. Our approach is based on the distorted wave impulse approximation in momentum space. The many-body medium effects are incorporated in the complex effective $\Delta$ self-energy, employing the results of the recently developed second-order pion-nucleus scattering potential. The experimental data for ${}^{12}$C and ${}^{40}$Ca are successfully described without the need to fit the model parameters of the photoproduction amplitude as a result of incorporating the second-order part of nuclear photoproduction potential, which involves intermediate nucleon spin-flip and charge exchange.

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Viacheslav Tsaran, Marc Vanderhaeghen. 2024-03-13. Nuclear coherent $\pi^0$ photoproduction with charge-exchange and spin-flip rescattering. https://doi.org/10.1103/physrevc.110.014605

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