Experimental Signatures of a New Channel of the Deuteron-Deuteron Reaction at Very Low Energy

IF 15.7 1区物理与天体物理 Q1 PHYSICS, MULTIDISCIPLINARY

Physical Review X Pub Date : 2025-10-07 DOI:10.1103/chlp-b215

R. Dubey, K. Czerski, Gokul Das H., A. Kowalska, N. Targosz-Sleczka, M. Kaczmarski, M. Valat

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引用次数: 0

Abstract

The discovery of a new, e+e− reaction channel in deuteron-deuteron (DD) fusion at very low energies might have major implications for understanding primordial and stellar nucleosynthesis, where electron-positron reaction channels are typically not considered. It could also enable research on metal hydride fusion, potentially paving the way for the design and construction of next-generation fusion energy sources. Following the first experimental indications of electron emission, we present here an extensive experimental study confirming emission of high-energy electrons from DD reaction at very low energy. A simultaneous use of Si charged particle detectors of different thicknesses and large-volume NaI(Tl) and HPGe detectors has allowed the determination of the branching ratios between emitted protons, neutrons, and e+e− pairs for deuteron energies down to 5 keV. The high-energy positrons could be unambiguously detected by their bremsstrahlung spectra and annihilation radiation, supported by the eant4 Monte Carlo simulations. The theoretical calculations, based on a destructive interference between the threshold resonance and the known broad resonance in He4, agree very well with experimentally observed increase of branching ratios for lowering projectile energies. The partial width of the threshold resonance for the internal e+e− pair creation should be at least 10 times larger than that of the proton channel.

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极低能量氘核-氘核反应新通道的实验特征

在极低能量的氘核-氘核（DD）聚变中发现了一个新的e+e−反应通道，这可能对理解原始和恒星核合成具有重大意义，在这些地方通常不考虑电子-正电子反应通道。它还可以促进金属氢化物聚变的研究，为下一代聚变能源的设计和建造铺平道路。继电子发射的第一个实验指示之后，我们在这里提出了一个广泛的实验研究，证实了DD反应在非常低的能量下发射高能电子。同时使用不同厚度的Si带电粒子探测器和大体积的NaI（Tl）和HPGe探测器，可以确定氘核能量低至5 keV时发射的质子、中子和e+e -对之间的分支比。高能正电子可以通过它们的轫致辐射光谱和湮灭辐射明确地探测到，并得到了eant4蒙特卡罗模拟的支持。理论计算基于He4中阈值共振和已知宽共振之间的破坏性干涉，与实验观察到的分支比的增加对降低弹射能量的影响非常吻合。内部e+e−对产生的阈值共振的部分宽度应至少大于质子通道的10倍。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Physical Review X PHYSICS, MULTIDISCIPLINARY-

CiteScore

24.60

自引率

1.60%

发文量

197

审稿时长

3 months

期刊介绍： Physical Review X (PRX) stands as an exclusively online, fully open-access journal, emphasizing innovation, quality, and enduring impact in the scientific content it disseminates. Devoted to showcasing a curated selection of papers from pure, applied, and interdisciplinary physics, PRX aims to feature work with the potential to shape current and future research while leaving a lasting and profound impact in their respective fields. Encompassing the entire spectrum of physics subject areas, PRX places a special focus on groundbreaking interdisciplinary research with broad-reaching influence.