120 / 2025-03-15 11:45:20

Alpha decay perturbations by electron screening in laser-heated clusters

α decay,laser field,electron screening,laser-matter interaction

The variation of nuclear decay rates under different environmental conditions has long been a subject of interest in the fields of nuclear physics, astrophysics, geological dating, and condensed matter physics. The advent and development of lasers have provided new opportunities for the study of regulating the decay rate of atomic nuclei. However, controlling nuclear decay rate by laser field remains challenging, as existing methods often require ultra-high intensity laser setups or are limited to low regulation efficiency.



Here, we propose a novel and efficient method to modulate the α-decay rate using laser-heated clusters. Initially, a cluster composed of α-emitting nuclei is irradiated by a laser pulse, inducing atom-ionization and rapid expansion over a few picoseconds. During this process, confined electrons within the cluster enhance Coulomb screening, increasing the α-decay rate. Particle-in-Cell (PIC) simulations demonstrate that the cluster expansion sustains a high-density core while diminishing electron temperature, thereby substantially amplifying the impact of screening effects on α decay. The deformed two-term proximity model predicts the changes in the penetrability of ²²⁶Ra from 2% to 7% under the laser intensity of 1.0×10¹⁵ W/cm², the modifications larger than that from direct laser field acceleration by six orders of magnitude. It is noteworthy that when the modification of the average change in penetrability reaches a level of 1%, the LDENI mechanism becomes equivalent to the DLNI mechanism in enhancing laser intensity by twelve orders of magnitude. Furthermore, by varying laser and cluster parameters, we perform a comparative analysis of direct laser-nucleus interactions (DLNI) versus laser-driven electron-nucleus interactions (LDENI) on the effects of α decay. The results indicate that laser intensity is an important basis for distinguishing the effects of these two mechanisms on α decay. These findings offer crucial theoretical insights for future experimental efforts aimed at controlling the α-decay rate assisted by lasers, potentially advancing applications in nuclear energy and fundamental physics research.