Isomer production by multi-photon excitation

Weitao Liu; Yuanbin Wu

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arXiv · 2504.18828

Isomer production by multi-photon excitation

Weitao Liu·Yuanbin Wu

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Abstract

The multi-photon excitation to the $8$-eV nuclear isomeric state $^{229\text{m}}$Th in the direct laser-nucleus interaction is investigated theoretically. We solve the time-dependent Schr\"odinger equation with the method which allows us to study the $n$-photon absorption in the nuclear excitation in the direct laser-nucleus interaction. Based on the laser facilities available currently or in the near future, we analyze the impact of the laser parameters on the excitation probability of the multi-photon excitation. The possibilities of the $2$-, $3$- and $4$-photon excitations to the isomeric state $^{229\text{m}}$Th from the ground state are discussed in details. Our results show the strong impact of the laser intensity and pulse duration on the multi-photon excitation probability. The onset of high-order effects in the multi-photon excitation in the direct laser-nucleus interaction is also revealed. Our findings open new possibilities to study the multi-photon laser-nucleus interaction in high-power laser facilities.

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Weitao Liu, Yuanbin Wu. 2025-04-26. Isomer production by multi-photon excitation. https://arxiv.org/abs/2504.18828

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