In the realm of energy research, understanding nuclear reactions is crucial for advancements in both fusion energy and astrophysics. Researchers Bahruz Suleymanli and Kutsal Bozkurt, affiliated with the University of Surrey, have recently published a study in the Journal of Physics G: Nuclear and Particle Physics that delves into the intricacies of proton-nucleus scattering, a process relevant to stellar reactions and, by extension, nuclear energy.
The researchers have developed a sophisticated mathematical framework, known as the Green’s function formalism, to precisely model and understand sub-barrier proton-nucleus resonant scattering. This approach allows them to solve the Dyson equation exactly, which is a significant achievement in the field of quantum mechanics. By using bare Green’s functions, they have mapped the complex quantum tunneling problem onto a more manageable scattering formalism. This method enables the summation of infinite quantum paths, recovering the exact tunneling coefficients and providing an analytical solution to the Dyson equation.
In their study, Suleymanli and Bozkurt applied this framework to three astrophysically relevant systems: proton interactions with lithium-7, nitrogen-14, and sodium-23 nuclei. Their model, which treats the strong nuclear force as a surface delta-shell impurity within the Coulomb field, achieved precise agreement with experimental resonance energies. For the heavier sodium-23 system, they found that the resonance energy is insensitive to the interaction strength, residing on a geometric plateau. Their calculated resonance energy of 2.11 MeV closely matches the experimental value of 2.08 MeV.
In contrast, the lighter lithium-7 and nitrogen-14 systems were found to be threshold states in a weak-coupling window. In this regime, the resonance energy is highly sensitive to the potential parameters and is sustained near the continuum edge. The researchers’ model yielded energies of 0.489 MeV and 1.067 MeV for these systems, respectively, closely reproducing the experimental benchmarks of 0.441 MeV and 1.058 MeV. These threshold states are characterized by a significant enhancement of the resonant cross-section, driven by the inverse relationship between the tunneling width and the spectral density peak.
The practical applications of this research for the energy sector are manifold. A deeper understanding of proton-nucleus interactions can lead to more accurate models of stellar reactions, which are crucial for nuclear astrophysics and the development of fusion energy. Moreover, the precise modeling of resonance energies can aid in the design and optimization of nuclear reactors and the development of advanced nuclear fuels. This research not only advances our fundamental understanding of nuclear physics but also paves the way for practical applications in the energy industry.
This article is based on research available at arXiv.