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arXiv · 2403.15387

Production of dark sector particles via resonant positron annihilation on atomic electrons

Fernando Arias-Aragón·Luc Darmé·Giovanni Grilli di Cortona·Enrico Nardi
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Abstract

Resonant positron annihilation on atomic electrons provides a powerful method to search for light new particles coupled to $e^+e^-$. Reliable estimates of production rates require a detailed characterization of electron momentum distributions. We describe a general method that harnesses the target material Compton profile to properly include electron velocity effects in resonant annihilation cross-sections. We additionally find that high $Z$ atoms can efficiently act as particle physics accelerators, providing a density of relativistic electrons that allows to extend by several times the experimental mass reach.

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Fernando Arias-Aragón, Luc Darmé, Giovanni Grilli di Cortona, Enrico Nardi. 2024-03-22. Production of dark sector particles via resonant positron annihilation on atomic electrons. https://arxiv.org/abs/2403.15387

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