A new scheme for isomer pumping and depletion with high-power lasers

Yang C.-J.; Spohr K. M.; Cernaianu M. O.; Doria D.; Ghenuche P.; Horný V.

doi:10.1063/5.0251667

Volume 10 Issue 5

Sep. 2025

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Yang C.-J., Spohr K. M., Cernaianu M. O., Doria D., Ghenuche P., Horný V.. A new scheme for isomer pumping and depletion with high-power lasers[J]. Matter and Radiation at Extremes, 2025, 10(5): 057201. doi: 10.1063/5.0251667

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Yang C.-J., Spohr K. M., Cernaianu M. O., Doria D., Ghenuche P., Horný V.. A new scheme for isomer pumping and depletion with high-power lasers[J]. Matter and Radiation at Extremes, 2025, 10(5): 057201. doi: 10.1063/5.0251667

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A new scheme for isomer pumping and depletion with high-power lasers

doi: 10.1063/5.0251667

Yang C.-J.^{1
,
,
,},
Spohr K. M.^{1, 2
,},
Cernaianu M. O.^1
,,
Doria D.^1
,,
Ghenuche P.^1
,,
Horný V.^1
,

1.
ELI-NP, “Horia Hulubei” National Institute for Physics and Nuclear Engineering, 30 Reactorului Street, RO-077125 Bucharest-Magurele, Romania
2.
School of Computing, Engineering and Physical Sciences, University of the West of Scotland, High Street, Paisley PA1 2BE, Scotland

More Information

Corresponding author: a)Author to whom correspondence should be addressed: chieh.jen@eli-np.ro
Received Date: 2024-12-04
Accepted Date: 2025-07-02

Available Online: 2025-11-28

Publish Date: 2025-09-01

Abstract

Abstract

We propose a novel scheme for the population and depletion of nuclear isomers. This scheme combines the γ photons with energies ≳10 keV emitted during the interaction of a contemporary high-intensity laser pulse with a plasma and one or multiple photon beams supplied by intense lasers. Owing to nonlinear effects, two- or multiphoton absorption dominates over the conventional multistep one-photon process for an optimized γ flash. Moreover, this nonlinear effect can be greatly enhanced with the help of externally supplied low-energy photons coming from another laser. These low-energy photons act such that the effective cross-section experienced by the γ photons becomes tunable, growing with the intensity I₀ of the beam. Assuming I₀ ∼ 10¹⁸ W⋅cm⁻² for the photon beam, an effective cross-section as large as 10⁻²¹–10⁻²⁸ cm² for the γ photons can be achieved. Thus, with state-of-the-art 10 PW laser facilities, the yields from two-photon absorption can reach 10⁶–10⁹ isomers per shot for selected states that are separated from their ground state by E2 transitions. Similar yields for transitions with higher multipolarities can be accommodated by multiphoton absorption with additional photons provided.

Conflict of Interest
The authors have no conflicts to disclose.
C.-J. Yang: Conceptualization (lead); Formal analysis (lead); Funding acquisition (lead); Investigation (lead); Methodology (lead); Writing – original draft (lead); Writing – review & editing (equal). K. M. Spohr: Conceptualization (lead); Formal analysis (lead); Investigation (lead); Methodology (lead); Writing – original draft (lead); Writing – review & editing (lead). M. O. Cernaianu: Investigation (supporting); Validation (equal). D. Doria: Conceptualization (supporting); Funding acquisition (equal); Supervision (equal); Validation (equal); Writing – review & editing (equal). P. Ghenuche: Methodology (supporting); Supervision (supporting); Validation (supporting). V. Horný: Investigation (equal); Validation (equal); Writing – original draft (supporting); Writing – review & editing (equal).
Author Contributions
The data that support the findings of this study are available within the article and its supplementary material.

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References(154)

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