40Ar fusion: A new route to producing key superheavy nuclei

Exploring  a New Approach to Synthesizing Superheavy Elements
Superheavy elements, found beyond uranium on the periodic table, are typically synthesized in laboratories using fusion reactions. Traditionally, scientists have relied on expensive and challenging-to-produce ⁴⁸Ca beams. In a new study, Jia-Xing Li and Professor Hong-Fei Zhang from Xi’an Jiaotong University propose using argon-⁴⁰Ar as a more cost-effective alternative. Their findings suggest that fusion reactions with ⁴⁰Ar can achieve evaporation residue cross sections comparable to, or even exceeding, those achieved with ⁴⁸Ca, while requiring significantly less beam energy.

Moving Toward the Creation of Element 119
Beyond element 114, the study also proposes a potential pathway for producing ²⁸⁶Mc, an isotope crucial to the alpha decay chain of element 119. By using the reaction ⁴⁰Ar + ²⁴⁹Bk, the researchers estimate that ²⁸⁶Mc could be synthesized with a relatively high cross section of about 7.9 picobarns. The successful creation of this isotope would be a significant step toward confirming the synthesis of element 119, marking a key milestone in the quest to discover and characterize superheavy elements.

A Detailed Fusion Process Analysis
To support their findings, the researchers employed advanced theoretical models to analyze the full fusion-evaporation process, which includes three primary stages: capture, fusion, and survival. The results indicate that ⁴⁰Ar-based reactions benefit from higher fusion probabilities and favorable inner fusion barrier dynamics. This advantage arises from the mass asymmetry between ⁴⁰Ar and the target nuclei, which facilitates the formation of a compound nucleus during the reaction.

Implications for Future Research
According to Professor Zhang, “⁴⁰Ar offers a new and exciting option for exploring the upper reaches of the periodic table. It’s not just a more affordable method—it could actually outperform ⁴⁸Ca in some reactions. This breakthrough has the potential to significantly impact the planning of future experiments.”

This research provides valuable theoretical insights for upcoming attempts to synthesize new elements and contributes to the broader understanding of nuclear stability at extreme atomic numbers. As the field continues to evolve, the use of ⁴⁰Ar may play a pivotal role in the discovery of new, heavier elements.

The complete study is accessible via DOI：10.1007/s41365-025-01719-y

Nuclear Science and Techniques (NST) is a peer-reviewed international journal sponsored by the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. The journal publishes high-quality research across a broad range of nuclear science disciplines, including nuclear physics, nuclear energy, accelerator physics, and nuclear electronics. Its Editor-in-Chief is the renowned physicist, Professor Yu-Gang Ma.